A/N Sherlock's often considered his body and everything else as merely transport for his brain. Then the transport starts to malfunction and everything goes to pieces. Everything comes apart.

Many thanks to my friend armydoctor for being my consult and providing me with the necessary medical information for this fic, as well as being my sounding board for ideas and possible tangents for the plot. Many a late night and a class time was spent asking her questions and screaming plot bunnies at her, and it was good. This is the longest I've ever written for a single chapter of a fic; it was simultaneously an absolute nightmare and one of my best writing experiences. I can only hope you think the same.

Recommended listenings for this work include: Fix You by Coldplay, Beside You by Marianas Trench, Slow Show by The National, and Hallelujah as covered by Bon Jovi.

Also available in Ao3 under the same username, and on Livejournal under the username aslowdumbshow.

I may have taken creative liberties with some symptoms and effects, but most of the information included here is as accurate as I can get it, given the limits of my research. Corrections and concrit will, of course, be welcome.

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Despite his medical degree, it is only when Sherlock Holmes drops his violin bow for the third time in an hour that John Watson realizes their life at Baker Street might be thrown into jeopardy.

John realizes afterward that "jeopardy" is a bit of an absurd notion. It's been a year since Sherlock "returned from the dead," gaunt and hollowed and weighed down by three years of hunting Moriarty's web; a year since John decked him in the face and stormed out of his new flat and returned two days later to find Sherlock curled up in his bed, hugging John's old oatmeal jumper. A year since John remembered once again what it was like to really live, and Sherlock, what it felt like to truly be warm. A patchy, awkward, stilted, progressive year.

John should have known the relative peace wouldn't last.

Sherlock bends down to retrieve the bow, and John sees it: a tremor in Sherlock's hand, not unlike the tremor John used to have before meeting the world's only consulting detective. It is minute, minor enough that if John had not been looking for something odd, he might not have caught it. But Sherlock has had no trauma (none enough to shake him, at the very least), has had no life-changing injuries, nothing that might haunt him. No "lack of" that might haunt him. And so this tremor means danger.

Sherlock fumbles with the bow – and has a very deliberate grip on the violin – and his eyes snap up to meet John's. They are icy, frozen over in a challenge, like bared teeth. Say it, they dare John. Go on, say it.

He doesn't. John only turns back to his laptop and his cup of tea, and can't help noticing his hands have tremors of their own. His hands are shaking. But John Watson has not had tremors since meeting Sherlock Holmes, and he is a doctor, and he knows that these are for different reasons entirely. So he types on resolutely, little taps with stocky fingers, and Sherlock goes back to playing whatever ear-grating melody he plays when he thinks.

Much later on, in the dark of one fateful night, John will wish he had said it. Said something. Anything.

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D.I. Lestrade is the next to notice.

Contrary to all of Sherlock's assertions, Lestrade is not an idiot. One does not become a Detective Inspector by not being sharp. He picks up when Sherlock struggles to open his magnifying glass so he can examine the victim's exposed toes. Lestrade asks Sherlock if he's feeling quite all right, to which Sherlock snaps an affirmative. This exchange does not go unnoticed by Anderson and Donovan, and all four of them – John included – see Sherlock dust off his palms and flex his fingers. But only John sees the planes of Sherlock's face go rigid, understands the glance of loathing Sherlock gives his hands. Sherlock crouches back down a little more stiffly than usual, yanks open his magnifying glass so forcefully he might have snapped it in half, and proceeds with his inspection. His speech is ever so slightly slowed as he enumerates his deductions. But other than a chillier tone than usual, there is no acknowledgment that anything has happened.

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Molly notices when Sherlock takes a whole minute to unzip a body bag. Donovan notices when she glimpses Sherlock taking very careful aim before grasping the yellow tape and lifting it up to let himself in. Mrs. Hudson notices when she goes up to the flat five minutes after Sherlock does and finds him still outside the door, letting himself in with a key that "won't go through the damn lock."

Mycroft's likely noticed even before John, and has simply been biding his time to confirm. Actually, knowing Mycroft, he probably picked up even before Sherlock himself, that posh, arrogant git.

Anderson, bless his tiny, unobservant mind, doesn't pick up at all.

Nobody acknowledges anything until the day John comes home from work to find Sherlock in his chair, fingers drumming on the arms, staring moodily at the phone on the table before him. "John," he says, by way of greeting.

"Sherlock," John replies, uncertain, waiting.

"I need you to send a text." Sherlock makes no move to hand over the phone, or point at the phone, or even flap a hand in its general direction like he normally does. In fact, his hands do not move from their perch on the armchair at all. John hesitates a few moments, then hangs up his coat and walks over. He picks up the mobile, but before Sherlock can dictate message or number John pulls up his soldier's courage and asks,

"Why?"

"Why do I always need you to send a text?" The tone is condescending, the accompanying look clearly stating don't be an idiot. But Sherlock is a crafty liar, so well-versed in the art that the only person he cannot convince otherwise is Mycroft, and that is because – loathe though he is to admit – his brother is more intelligent than he, and possibly knows him almost better than he knows himself.

John's witnessed him sham enough times, though, and he decides to call Sherlock's bluff. "That's not why. Not this time."

"John." His tone clearly spells warning, tells John to drop this now. But John can be as stubborn as Sherlock when he means to be, and now he definitely means to be.

"Sherlock." John stares him down, the higher one up for once. "Why can't you send the text?"

Anger flashes over Sherlock's face, but John does not back down and they glare at each other, an impasse. For the longest while there is silence and a showdown by their eyes, and John feels for a moment he might have pressed too hard, but he stands resolute. Then Sherlock sighs and turns his head away. His fingers continue to drum out unintelligible patterns on the armrests. "I cannot," he whispers, his face tightening, cheeks flushing.

"Why," John insists. His voice is hard-edged from the fight to keep it steady

Sherlock exhales noisily, and moves one hand up from its perch. Without something to do or hold on to, the hand begins to tremble. Flinching, Sherlock curls the hand into a first and all but slams it back down. "I cannot," he repeats, with much less fight and more something akin to defeat in his voice.

John ends up making plenty of typographical errors in the message to Lestrade because he refuses to remove his gaze from Sherlock's, whose eyes tell everything his words and body will not: that Sherlock is afraid, and Sherlock feels lost.

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You all right, mate? Could barely read the text you sent for Sherlock. GL

Fine. Just too tired to be arsed to correct things. You know how it is. JW

What about Sherlock? During the last case, he – well. Yeah. GL

Fine. He's fine. We're both fine. JW

Suit yourselves. GL

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Sherlock refuses to go to the hospital.

"I know what you think it is," he observes aloud, in the kitchen, after John nags him for the third time that week to maybe get checked, a few months after that day Sherlock dropped the violin bow. "And so do you. You are a doctor; you've probably diagnosed me yourself."

"I'm an army doctor. I handle trauma and quick, dirty surgeries. I'm not qualified to diagnose something this major." John notices both he and Sherlock avoid mentioning what it and this really is. "It might not even be for sure."

"We are both aware of the symptoms. I've stumbled thrice while chasing a criminal, fallen down once. I appear to struggle to get up from the bed or the couch, and to play the violin." Sherlock peers down through the microscope, his fingers busy fiddling even though he only has to hold the knobs still. Even from where he stands, across the kitchen counter, John can see Sherlock blink repeatedly, unable to focus completely on the sample through the lenses of the scope. "But they could mean anything. It's fairly difficult to give a prognosis on this."

"Sherlock!" John can feel his doctor's instincts team up with his need for Sherlock to be all right. Because this – and John can't even refer to it properly in his mind – is more than just the usual tussle with a criminal, where his maddening flatmate didn't duck in time to avoid a punch or found himself on the business end of a kitchen knife. John, however grudgingly and exasperatedly, can handle that himself, put Sherlock back together under the harsh lights of the bathroom. This is much bigger than that, much more serious, and much scarier, for the both of them. Almost six years of knowing Sherlock haven't improved John's deductive abilities with regard to the world at large, but he can manage Sherlock just fine; John can read in the clench of Sherlock's jaw, the barely perceptible tightening of his lips, that Sherlock knows he is blinking too much, finds it difficult to see with his usual clarity, and that frustrates him. It frustrates John, too.

"And I know you're watching me blink," Sherlock adds quietly, still resolutely not looking up. The first three fingers on his right hand spasm, and John grits his teeth against the fresh surge of – of – of whatever emotional cocktail threatens to rise up in his throat. Anger, dread, pain, desperation. Sherlock squeezes his eyes shut, seems to war with himself for a bit, then abruptly shoves the microscope at John so hard it grates the table. "Now look at this blood sample and tell me if you think there's something odd. The identity of a murderer depends on it."

There is an awkward standstill of time in the kitchen as Sherlock has one arm outstretched, fingertips resting lightly on the body of the microscope, examining the countertop as if trying to deduce the life of the worker who made it, and John has his hands fisted at his sides and his own eyes trained on Sherlock as if he can't bear to look away. Then John sees Sherlock's arm start to quake under the strain and under – under this – and so he takes the microscope as gently as he can and peers into the lenses.

"Anemic, perhaps," he says offhandedly, twiddling the knobs to get a sharper image.

"That's what I saw, too," Sherlock replies, and with the barest of struggles, gets up to leave. There is a silence in which they both pretend what he said is true.

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Check husband's medical records. If anemic, arrest wife. SH

Took a while, didn't that? We've been trailing the wrong person for two bloody days. GL

Got a new case, by the way. Serial break-ins down in Kensington. Five houses hit, nothing stolen, only men's suits trashed. Slashes seem to have a pattern. Will you come? GL

Oi, Sherlock. GL

Hello? GL

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Just because Sherlock refuses to consult the medical community with regard to his problems, doesn't mean John can't do it for him. He's not a doctor for nothing, after all.

He reads the medical texts at work, digs up journals the clinic's doctors are always saying they'll read but never really get around to opening. As casually as he can, he borrows books from St. Bart's resident neurologist, claiming boredom with his locum work. He browses during the downtimes of his shifts, sometimes forgetting his paperwork entirely while immersed in his studies. They're not much – the texts they've got are a bit old, the journal issues not regularly updated, and what books he can borrow can't be held for long – but they're informative enough, and John can fill the missing holes in his research through the internet. He's considering having a bit of a chat with the neuro, a pleasant man named Dr. D. Shepherd, and casually asking after certain neurological degenerative diseases one of these days. Only for curiosity, of course (whatever he needs to tell himself).

Then one day they come home from a case that Sherlock dismisses as "mind-numbingly dull and moronic" (even though it takes him a full three minutes longer than it normally should to profile the victim, and he abruptly drops to his knees instead of his usual crouch when he bends to examine the body) to find a small stack of medical journals sitting innocently on their coffee table. Sherlock only has to glance at the title of the topmost paper (Understanding Self-Assembly of Tiny Biological Machinery and Its Connections to Developments of Methods in Treating Neurological Diseases at Nanoscale) before he realizes what they are and what they mean – and subsequently, who they are from. He snarls, smacks the whole pile off the table, and whirls around, bullying for the stairs. It takes nearly all of John's considerable strength to stop him from thundering out of the flat like a stampeding rhino.

"Sherlock – what the hell – calm down, you daft git!"

"Mycroft," Sherlock growls, determinedly pushing his height advantage to try and bypass John. Fury makes his pale skin come out splotchy and his tremors become more pronounced. A muscle twitches in his jaw, and coupled with his wind-mussed hair and angry eyes, makes him look positively demented.

"Mycroft what?" John asks, herding Sherlock into the flat and onto the couch. Sherlock's hands clench and unclench; his knee jiggles up and down erratically. He tries to get back up but John gets one knee on his thigh, and a hand on his shoulder, and a brief struggle finds them nose-to-nose with John practically straddling Sherlock on the couch. "What, Sherlock?"

In response, Sherlock stabs a shaking finger at the offending articles where they lie scattered on their living room floor. John cranes his neck, unwilling to get up and look lest Sherlock jump up and escape, and reads the title on the closest sheet: Symptomatic Differentiation of Idiopathic Parkinson's Disease (or Primary Parkinsonism) and Progressive Supranuclear Palsy (Steele-Richardson-Olszewski). There was an extract from that article in a periodical he'd read last week; he hadn't managed to get his hands on the whole article because the clinic didn't carry such specialized references. As he skims the other titles, catching words such as substantia nigra and norepinephrine and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyrine, he realizes these are all copies of the leading publications on neurological disorders. Specifically on Idiopathic Parkinson's Disease. PD.

Nice, subtle little message from Mycroft, this.

There's a flurry of movement beneath him and before he can refocus his attention on Sherlock, John is upended and unceremoniously dumped onto the floor. Sherlock drops to his knees, muttering about a note, crawling and scrabbling through the papers and booklets, rustling them into an even bigger mess. John's eyes widen in comprehension and he starts searching too. His eyes spot it scant seconds before Sherlock snatches it up, and not for the first time he was just a little faster than his flatmate, because at the front of the envelope, in Mycroft's stiff, diplomatic handwriting, are the words For Dr. J.H. Watson, MD.

For what seems like an eternity Sherlock stares at the envelope in his hands, head bowed, face shadowed by his dark curls, and John stares at Sherlock, mind awhirl with trying to figure out what to say. Then Sherlock promptly drops the note, which flutters down unsatisfactorily (John knows Sherlock would rather it fell with a prominent thwack), fumbles to his feet, and in a dramatic swirl of coat, strides off to his bedroom. The door is slammed before John can so much as say his name.

Since John had bullied him onto the couch, Sherlock hadn't looked at John, not once.

Quietly, guiltily (though what for? It isn't as if he asked for these), John tidies up the articles, shuffles them together, and lays them on the desk by his laptop. He goes into the kitchen and puts the kettle on, searching the cupboards for clean cups. Along the way he notices that the experiments that require more finesse and dexterous fiddling (things involving pipettes and precisely dispensed chemicals and steady hands) have been abandoned, lying in various states of decomposition and degeneration. This discovery shakes John almost as much as Mycroft's little present, because experiments are what Sherlock distracts himself with when The Work is not around. And Sherlock has stopped their progress completely.

Sherlock is giving them up.

John's stubborn flatmate might not wish to consult with a specialist, but he's not committed years of medical knowledge to memory for nothing. And if there's one thing his genius brain can't give him, it's the denial of something he wishes wasn't true. Sherlock is incredibly gifted in the ability to lie to others, but he lacks the 'pedantic' capacity to lie to himself.

And on this, John can't lie for the both of them. He couldn't, even if he hadn't taken the Hippocratic Oath.

The kettle boils. John makes two cups of tea, sets the other one out on the counter, sips his. When that's done and the other cup's gone cold, he makes another batch. Then a third. By the fourth he's simply setting out one cup and staring at it from across the counter like it's got all the answers.

Hours and eight wasted cups of tea later, the flat is dark and Sherlock has not emerged from his room.

John picks up his laptop and the sheaf of publications and brings them up to his room. He spends the night half reading and half listening for any signs of life from Sherlock. Half the terms in the journals are vaguely familiar to him, skimmed over during his foundations, shunted to the back of his mind because he hadn't needed things like glutamic acid decarboxylase and mitochondrial oxidative stress in trauma surgery and on the battlefield; the other half (mostly the genes and the treatment chemicals) are completely over his head. But he slogs it through, looking things up online and in long-unused textbooks, and in the end knows more than he'd ever wish to, but he knows.

He knows, and at the center of the information whirlwind in his mind is Sherlock, Sherlock and his shaking hands and too much blinking. Sherlock who'd walked out on him for wanting to know. Sherlock, his flatmate and his best friend and –

The dawn breaks and but for the rustle of paper, the flat is utterly silent.

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The first day of Sherlock's self-imposed isolation, John tries to go about his business as normal. His only deviation from routine is to stop by Mrs. Hudson's flat and tell her to give him a ring should Sherlock decide to rejoin the world of the living. She promises to do so and to bring the "odd little man" a few biscuits and maybe tea if he emerges. John pats her on the shoulder and kisses her cheek and leaves for work.

There is no joke about their having "a little domestic" and it hits John again, how much Mrs. Hudson really cares for Sherlock. She'd forgiven him rather quickly for reappearing from the dead, herself. And she sees much more than either of them usually gives her credit for. It unnerves John a bit.

Sarah's noticed he's been delving a bit into neuroscience and makes a joke about a late change in career. John barely manages a polite smile as he shrugs it off. Her smile falters at his less-than-friendly response, and she hands over the most recently acquired journal (a neuro digest published six months ago) without further comment.

During his extended lunch break he manages to catch Dr. Shepherd in the Bart's cafeteria, and under the guise of a consult for a patient who'd come in to be treated for the flu but exhibited signs of PD, wrings out a little more information. He goes back to his little office in his little clinic with its little medical concerns, and not for the first time, but perhaps this time truly seriously and painfully, wishes he were not a doctor, so he wouldn't understand so thoroughly what all his research means. It wrecks him, this new knowledge, in a way it shouldn't – he is a doctor, he ought to welcome new knowledge, ought to revel in the fact that he's learned something novel and stimulating. He's putting his mind to something he loves: learning medicine.

But that this knowledge is all for Sherlock, applies to Sherlock, and tells him in neat, clinical terms what can and will happen to Sherlock – that makes the bile rise in John's throat, makes him loathe his understanding of this knowledge. Even without the extra research, he'd have a general idea of what PD does to a person. He knows the tremors, difficulty initiating movement, and stiff limbs; knows the gradual development of bradykinesia, dementia, and dystonia; knows the eventual muscle atrophy and disability development. He knows that Sherlock's brilliant, wonderful mind will cease being able to send signals to his body, that his mind will want him to see and do this but his organs cannot carry out the acts. Sherlock's genius will be trapped in a body that will refuse to function.

And what terrifies John the most is that it could happen at any time, because the progression of PD could take anywhere from months to years. Could be linear or exponential. They'll never be certain, will always be watching and hoping and waiting. And even if he's Sherlock's doctor, he isn't qualified to do anything about it. There's nothing he can provide, nothing he can offer. He can do the research, learn the facts, but that's all he's going to have. Knowledge is all he can give Sherlock, and even that's futile because Sherlock already knows most of this himself.

Sherlock could be dying and John is useless.

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Security cameras reporting static from Sherlock's room. Problem? MH

Bugger off. JW

There's an upcoming conference on neurodegenerative diseases in Nice. Sherlock does like France at this time of year. MH

No, thank you. Bugger off. JW

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By the next day, John is starting to fray at the edges. He has today and tomorrow off from work, claiming Sherlock problems (true), leaving Sarah to assume Sherlock's gotten himself a beating or blown himself up as usual (untrue but convenient). He's slept restlessly, unused to the quiet; he's bemoaned Sherlock's violin playing before, but now he couldn't be more grateful if he were to hear Mendelssohn at four in the morning. During his waking periods he's assailed by continued thoughts of how all of this is beyond his skill to fix. By the time gray light starts peeking into his pale blue curtains, he's fuming at himself, Parkinson, the medical community, Mycroft, and whichever chromosome of Sherlock's decided to take the piss and trigger the protracted meltdown of his body. The patter of his feet on the stairs echoes through the whole flat. He briefly considers a cup of tea (what's left of his sense of humor chuckles at him and says English courage) but bypasses the kitchen determinedly and strides right up to the door of Sherlock's room.

It is unlocked.

At the back of his mind he realizes that two nights ago he hadn't heard it lock.

Bugger.

"Sherlock?" John pushes the door open gently, peering inside. He's greeted by faint light and silence. The room is just as he remembers: Spartan but for the cluttered shelves, periodic table up on the wall, closet organized in ways unfathomable to "ordinary" human minds. The window is open, curtain fluttering in the breeze. There is no sign of Sherlock anywhere.

His phone buzzes in his pocket and he nearly sends it flying in his haste to check the message.

Have just received report of person matching Sherlock's description purchasing illicit substance outside perimeter of drug ban. If no word from you in five hours, activating Plan R. MH

Plan R. R for Relapse.

Shit. Shit, shit, shit.

John races back to his room, yanks a haphazard combination of clothing from the closet and tugs them all on, getting his jumper on inside out and his socks mismatched in his rush to get dressed. With all the noise he's making (swearing, bumping and tripping all over the place), he doesn't notice the flat door open and close, or the quiet, measured steps on the stairs. He only notices anything, in fact, when he barrels down the stairs with his arms contorting into his jacket, and abruptly slams into all six feet of infuriating, reckless consulting detective, sending him reeling back into the landing wall and John himself flumping down onto the steps.

"John," Sherlock gasps, and while part of John is rather pleased at the fact that he's managed to surprise Sherlock, the rest of him is catching up with the situation and rapidly becoming piss fucking livid. Before Sherlock can make his excuses or escape, John's up and crowding into his personal space, breathing down his throat like an angry bull.

"Pockets," he spits out, glaring up at Sherlock. The doctor in him notes the intermittent twitch in Sherlock's hands, and the tiny jumps in his right leg, and the clarity of his eyes – not high, not yet – but the soldier in him can only think drugs and promised to stay clean and what the fuck were you thinking? Doctor knows this is an understandable reaction but Captain hates that Sherlock sank so low right away.

Sherlock hasn't moved, hasn't reacted, has the gall to glower at John sullenly, as if John's the one who went and did something reckless and utterly stupid and –"POCKETS!" John yells, bulldozing over any thought of discretion.

Sherlock snarls, John pounces and they tussle on the landing. Sherlock has at least a head over John and much more grace but John wasn't a captain in the army for nothing and he's much stronger, has far more bulk to throw, so it ends with Sherlock pinned front-first against the wall, arm twisted behind his back, and John ignoring his black eye and rifling through Sherlock's coat. There might have been sexual tension if the two of them weren't so bloody furious.

The tiny Ziploc ends up being in the inside pocket of Sherlock's blazer, and once John's got it out, Sherlock shoves him off and hunches in the corner, cheeks splotchy from anger and humiliation. The packet is three quarters full with fine powder, and John catches a tiny H scribbled on the edge. Heroin, not cocaine, Dr. Watson assesses, opiate, not stimulant, not now. He needs something to dull, not sharpen.

Sherlock is looking at John peculiarly, in a mix of guilt and defiance. It is the same look, John realizes, as the one he'd given John that day he dropped the bow. Say it, he's daring John again. Go on, say it.

John takes him up on the challenge. His flatmate's always faulted him for asking and pointing out the obvious, so he goes right ahead and gives him another reason to do so. "What," he grates out, staring daggers at Sherlock and brandishing the Ziploc between them, "is this?"

"I should think it would be obvious," Sherlock snaps, crossing his arms tightly over himself. He at least has the compunction to struggle to meet John's eyes. "Surely you don't actually need me to clarify the situation this time, however pitiful your powers of observation are."

"Sherlock," John warns, low rumble in his throat. In response, his flatmate merely arches an eyebrow, trying to gun for his usual condescending and mocking expression. It's ruined, though, by the twitch in his jaw and a wince.

John clenches his fingers around the tiny plastic bag, feeling oddly betrayed. As a doctor he knows this kind of patient attitude; having served in the army, he's all too familiar with it. It's a strange combination of denial of the condition and surrender to the disease; the patient simply doesn't give a damn and despairs of hope. And while John can't blame Sherlock for feeling miserable – it's even a side condition of PD, so it's excusable – he really has expected better of him. Expected his genius mind to try and outstrip the progression, expected Sherlock to fight. To take his bright energy and channel it into staying ahead of his degeneration as long as possible.

"What the bloody hell were you – no, no, don't answer that. Obviously you weren't, you didn't want to." John can feel the tautness on his back as he holds himself rigid, holds back the worst of his fury. He takes in a shaky breath. It doesn't work. "What the fuck did you hope to achieve by shooting yourself up with – what was this going to do? You can't just shut your body down the way you hope to do with your mind – that isn't how it fucking works – you can't just drug the shaking away–"

"Yes, and you would know all about tremors, wouldn't you, Captain Watson?" Sherlock's base retort hits like a blow to the solar plexus and that's it, John's seeing red. PD has nothing on PTSD, they both know, but at least John wasn't in denial about his condition.

"No. No, you don't get to go there, Sherlock Holmes. You don't fucking get to go there. You don't fucking get to manipulate this conversation and weasel your way out of this. Just – just no." Sherlock opens his mouth to sneer but John's fist slams down on the banister and that shuts him up. "Stuff it. This – this is beyond not good – this is so fucking stupid Anderson has nothing on it. The next thing I want to hear when you open that smart-aleck mouth of yours is why the hell you thought this was a good idea. So."

John pins his hands under his arms to prevent him from doing anything regrettable once whatever snide response Sherlock has waiting at the tip of his tongue comes out. Wise move; Sherlock's next words are, "what, can't tell a medication attempt when you see one, doctor?"

"You utter bas– YOU DON'T MEDICATE PARKINSON'S DISEASE WITH HEROIN!" John bellows, and then abruptly snaps his jaw shut, horrified. That's it, then. It's up there now between them, thrown into both their faces. It has finally been properly named out loud. Sherlock blanches; his face drains of color, rendering him bone-white with fury. Fuck.

"Sherlock–" But there's a thud and abruptly the ground teeters beneath John as he's thrust backwards, catching his ankles on the bottom step and toppling over. When he recovers from the shock all he sees is a whirl of coat and dark curls as Sherlock thunders down the stairs. The slam of the front door feels like another bullet to the shoulder.

Well if this isn't just peachy.

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Where's Sherlock? Fourth child kidnapping reported in two weeks, all similar circumstances, no ransom notes. Need him to examine crime scene. GL

John? GL

Bloody hell, not you too. GL

Don't make me execute a missing persons search. GL

Bogged down at clinic. No idea about Sherlock. Sorry. JW

What's gotten into him, anyway? He's been acting oddly lately, even for him. Fifth crime he hasn't responded to. GL

Oh, for the love of god. GL

Right. I'll get the warrant. GL

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True to his word Lestrade shows up at the flat a few minutes after John gets home, but he shows up alone and in casual clothes. It's clear from the look on his face that he doesn't expect Sherlock to be around. John's taking a cup of tea in his armchair, having pointedly made enough for one, and nursing his sulk. There's been no sign of Sherlock for three days, and John assuages his guilty thoughts by reminding himself every so often that there's been no word from Mycroft either. The elder Holmes is nothing if not thorough, and if Sherlock were to get up to anything John would surely be informed.

"Having a bit of a stiff, then, yeah?" Lestrade asks, glancing around the flat with his hands on his hips. It wouldn't take a genius to see that, but John knows there are many more layers to Lestrade's question that can be taken at face value. The D.I. is more perceptive than Sherlock gives him credit for, and between communication or lack thereof with John and Sherlock, and what he's seen at crime scenes, he's probably put together a moderately accurate picture. "All right, don't answer that, it's obvious. Even Anderson could pick it up if he bothered. What's he gone and done now?"

John's response is a tight smile and another sip of tea. He'd given a similar response to Mrs. Hudson when she'd come up yesterday, all smiles and reassurances and "oh, he'll come around, we both know what he's like when he works himself into a tizzy." He's not sure if he doesn't answer out of protectiveness of Sherlock or because he's segueing from angry to shamefaced, or some reason he hasn't managed to fathom just yet.

Lestrade steels himself with a deep breath. "Right. Well." He purses his lips, shuffles his feet, and looks John squarely in the eye. "This – it's big, isn't it? What he's got. I mean – I've not got a doctor's degree but I'm divorced, which means I've seen enough episodes of House and The Doctors to guess at what's going on, and, well – it's Sherlock. Is he all right?"

It speaks volumes of Lestrade's regard and exasperated affection for the consulting detective, what he's just asked, and how he's asked it. It also intensifies the muffins of guilt in John's gut, because no, he doesn't know if Sherlock's all right. He doesn't even know where Sherlock is, let alone how he's doing. John's silence and the sudden pinch in his expression tell Lestrade all he needs to know. "Right." He shuffles again, awkwardly, and clears his throat. "Meaning no offense by asking this, though, but he isn't–" He breaks off, runs a hand through his salt-and-pepper hair, tries again. "I mean, I trust the guy, yeah, but he's not – he hasn't–"

What – oh. "No – no. He –" He what? He tried but John had caught him out and they'd had a row on the landing and that's why Sherlock isn't here? "He's not." John smiles tightly up at Lestrade, who holds his gaze for a moment before seeming satisfied and nodding.

"Sorry. I mean – the – well it could look like he, you know–" Lestrade looks relieved when John holds up a hand and shakes his head to cut him off. The D.I. is a good man and despite his experiences with Sherlock it's obvious he wants to think the best of him, which includes not wanting to believe he may have lapsed back into habits that are less than desirable. "You'd tell me if – well, you would, wouldn't you?"

"Mm." John sets down his cup, belatedly realizing he hasn't offered Lestrade one. He wonders if he should, but then Lestrade will likely leave soon anyway.

"So – do I send out the missing person report, then? Dispatch a team? Get my sniffer dog?"

John recognizes the effort to make as little a deal out of this as possible, and it actually makes him crack a smile. "No, no. It's fine. He's fine. We're fine." He exhales sharply, stares at his cup going cold. Feels himself going cold, because the muffins in his gut are freezing over and Sherlock's still not here. "It's all fine." Lie.

Lestrade opens his mouth, closes it, looks helplessly at the skull on the far wall as if it will have answers, then heaves a very weighted sigh. "Well, just…" He trails off, looking very much like he doesn't actually know what he wanted to say. Likely he didn't. "Just – take care, the both of you. Sherlock's a tosser and you're a bit mad yourself, but God help me if I wouldn't move the earth or at least Scotland Yard to make sure you're all right."

And with that uncomfortably affectionate, bumbling confession, Lestrade half-raises his hand and grimaces a little. An awkward half-second later, he just nods and leaves. John is rather thankful, partly because Lestrade wasn't making him feel better in the slightest, but mostly because Lestrade's hasty departure prevents John from acting upon the very strong and discomfiting urge to give the Detective Inspector a desperate hug.

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Back when they were kids, John and Harry used to get into the worst of fights. It was the foundation of their relationship as siblings. They'd fight over Harry coloring John's kiddy science books pink and purple and glittery, over John tripping her up when they'd play ball in the yard, over John getting to ride the bike first or Harry getting the bigger cookie, and once, when they were older and Harry was newly out of uni, over how John hadn't spoken up when their parents were shitting their heads off over Harry's coming out. That same night Harry had gone off on her worst drink binge that year, crashed their shared car into a tree, and bashed her head against the window. Up to that day John had been a master sulker, able to hold onto his anger and resentment for days on end until Harry (no matter who was at fault, it was always Harry) caved and apologized in some whacked-up Watson way. (John's favorite had always been Lara, pretty Lara and one of the best dates John's been on in his life.) Up to that day John could indulge his temper better than Achilles during the war of Troy. But being called off his intern rounds to report to the ICU and being told by his resident that no, it wasn't Mr. Trevor again, it was a Miss Harry Watson and was she his sister, was more than enough to cop John's months-long funk and send him hurtling through the corridors faster than someone on his first forty-eight hour shift in the trauma ward should be able to run.

Between that and getting shipped off to the Middle East, where dying at any second was a very real possibility, John's learned to never nurse a sulk again.

This is why, three days after the massive row, John grits his teeth, clicks open his phone, and voluntarily texts the one person he'd rather not have to initiate contact with unless his or Sherlock's life depended on it. He rather hopes that scenario isn't true.

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Three days no contact from S. Thought you said you'd wait five hours? JW

Report was accurate, then? Had expected you to sort it out yourselves. Sherlock is quite fond of reminding me that you both are perfectly capable of managing your own lives. MH

Why don't you focus less on being a fucking git and more on finding your own little brother? JW

Language, John. Language. MH

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Two days later, Sherlock returns to the flat, though whether by his own volition or by being forced, John doesn't know and doesn't ask. His stuttered, fumbled greeting is met with icy silence; in fact it is a week before Sherlock responds in any form at all. For that week John leaves out cup after cup of tea, and tidies the flat until you can eat off what portions of floor are available, and even rearranges the fridge to allow for the various decomposing body parts to be accommodated more freely. But Sherlock remains withdrawn, rarely emerging from his room if at all, and doesn't take on a single case. At first John thinks this is because he's sulking. Then considers it might be because he's still wallowing in self-loathing. It takes a sweep of Sherlock's room, one rare afternoon when he'd left without saying a word (it was clean), and a surprising discovery of the toothpaste tube behind the toilet, still half full but with the screwed-on cap mangled, for John to realize why Sherlock's holing up.

He's getting worse.

It's been more or less a year since the day Sherlock dropped the bow and John had the first inkling that something might be terribly wrong. Long enough for the symptoms to progress; long enough for Sherlock to realize the impending deterioration of his physical faculties, rebel against the thought, then bitterly have the facts thrown into his face with no choice but to accept them. Whatever happened in the five days Sherlock had disappeared, it has made him rigidly aware of his own condition and the limited options available to him. Those five days have also reminded John of just how useless he is in their situation.

He clutches the toothpaste tube in his hands and tries to keep the sob welling in his throat very quiet.

The briefest glimpse of dark curls in the mirror, and the rustle of coat and rapid footsteps outside the bathroom door, tell John he did not succeed.

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Am I going to have to find a new consulting detective or is the current one going to get off his arse and come help? GL

Ambassador's daughter kidnapped, forensics team haven't found anything to go on at the site. End of my tether here. GL

Just about ready to bribe you with cigarettes. GL

Five minutes. SH

Ah.

I wasn't serious about the cigarettes. GL

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John's sitting at the kitchen table, brooding over his coffee (something stronger than tea is rather necessary after the nights he's been having) and biscuits, when Sherlock bustles out of his room, fully dressed for the first time in a week. He's tugging on his gloves and looking around for his scarf, but he's in the kitchen and making tentative, grumbling sort of noises that tell John they're half frustration over the missing bit of fabric and half attempts at actual speech. He sips his coffee patiently, trains his eyes on the biscuits as if they're a fascinating cardiovascular breakthrough, and tries to look as non-threatening as possible. It's an easy feat in his wooly jumper and weary expression.

By now Sherlock's just hovering by the kitchen table, fiddling with his coat collar, flipping it up and down over and over (a voice in his head: you being all mysterious with your – cheekbones, and turning your coat collar up so you look cool, feeling like a lifetime ago). His cheeks are lightly flushed pink and his jaw is twitching, and it's a moment before John realizes it might not be from the PD. It tugs at his heartstrings, does Sherlock not knowing what to do, and so with a put-upon but amused sigh, John sets down his cup.

"Crime scene, then, yeah?"

Sherlock looks up, face rendered young and boyish by the hopeful expression in his eyes, even as he presses his lips together. His hands tremble at his lapels but John refuses to look. He knows an apology when he sees one, even the Sherlockian version of it. He slides off the kitchen stool, deposits the cup in the sink and the biscuits in the fridge (next to Sherlock's plastic container of rainwater-soaked thumbs) and goes for his coat.

For the first time since they came home to Mycroft's little gift, Sherlock smiles.

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Dinner at the flat finds them both in high spirits. It's been two days since the start of the case and Sherlock, with his usual triumphant nature, manages to narrow the kidnapper down even with almost no evidence (even for him) at the crime scene. As the Yard goes off to arrest the ambassador's chauffeur, John and Sherlock return home for their usual post-case meal (one of the rare times John will ever get Sherlock to willingly eat), and if they forego their usual Chinese then John does not comment on how it might be because Sherlock cannot use the chopsticks. They get curry, and Sherlock demolishes six pieces of nan, and they eat while watching a few episodes of Criminal Minds. John times how much faster Sherlock profiles the killer than Hotchner and the team, and Sherlock mocks John's reactions to the emotional plot. When John tears up at Haley's death, however, Sherlock is quiet.

Later, Sherlock tidies away his dishes and cutlery without John's nagging, and even makes a halfhearted attempt at shifting a few experiments to less inconvenient and health-threatening locations. His fingers linger a little on the experiments he's abandoned, but neither of them says anything. It doesn't sit right with John – he is a doctor, he should be advocating medicine and not pity – but he lets it go for now. He figures they both need one night without the reality of Sherlock's condition staring them in the face. They smile, and Sherlock actually says good night first, and John goes to bed feeling warmer in his chest than he can ever remember being when a woman tells him she loves him.

He sleeps less restlessly that night, and if the Bach at four in the morning falters more than a little, well, John's just happy to hear it at all.

But when he comes down in the morning for breakfast and tea, it takes him a moment to realize why the kitchen seems cleaner. Around half the experiments have disappeared; the kitchen counter holds only two stacks of paper weighed down by a few pieces of Sherlock's rock collection and six beakers filled with colorful liquid. Sherlock offers no explanation and John asks no questions, but when Sherlock leaves to take a shower, John takes a moment to sit down and collect himself. There are only so many wordless acknowledgements a man can take before they start to wear at his heart.

He stares the tidied surfaces and wonders just how much time is left before the mutual silence must end.

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The next few consults with the Yard are uneventful – or at least, no more eventful than they were before all this started. Aside from stiffness and rapid blinking, Sherlock manages to function normally. He patronizes Donovan, insults Anderson, snipes at Lestrade and makes the whole room feel like they're idiots. John, however, is more cheerful than he's been in months (more than is polite at a crime scene, but he doesn't care). Everything, for now, is good.

And then one day, after a week without cases wherein Sherlock is oddly subdued and inactive, they're called down to the Thames to inspect the body of one Miles Jeevas, a minor official in the British government (John has to wonder if they mean it literally or in a Mycroft sort of way) who's been missing two whole days. The outgoing tide exposed the body. Sherlock whips out his little magnifying glass while John hears Lestrade out. The conversation goes from the details of the crime to the latest Manchester United match, until it's a good ten minutes before they remember Sherlock's profiling the victim.

To their surprise, when they turn, Sherlock's still kneeling by the corpse, hands clutching the glass over the left eyebrow.

"Sherlock?" Lestrade breaks the silence first, but John beats him to figuring out what's wrong, and it makes the panic break open in his chest. He knows the Yard is waiting for Sherlock to sweep to his feet and rattle of his deductions as per usual, pointing out any number of things nobody has seen and bringing them together to a conclusion nobody will have thought of but is inexorably correct. But Sherlock remains kneeling, clicking his magnifier shut very deliberately, with hands that tremble both from effort and from a disease that is now inching out of his control.

There is a brief moment when John feels his heart is too big for his chest, and then he steels himself. Then, knowing full well that Sherlock might wholly despise him for what he's about to do, he strides over to his friend and thrusts out an arm.

If looks could kill, John would be utterly obliterated and in seconds from the death glare Sherlock sends his way.

"Sherlock," he says, very quietly and very patiently, jerking his arm to reassert his offer. He can feel the eyes of the assembled police force on the both of them, every last pair, all of them wondering what the hell is going on and if they're to do anything about it. Any second now the pieces will click in Lestrade's head, and John needs to get this done before that happens. "Just get it over with, all right?"

There is a very long, very tense silence in which the Yard stares at John and John stares at Sherlock and Sherlock stares at the corpse's clavicle as if it has the answers to the universe. John thinks that he has never, not ever (not even when he'd come back to his new flat to Sherlock huddled in his covers, clutching his jumper, and staring up at him with words he didn't know how to say) seen Sherlock look like this: openly lost, vulnerable and helpless.

Right. In for a penny, in for a pound, then.

Setting his jaw, John gives Sherlock one more chance to voluntarily take his hand and get to his feet. When Sherlock does nothing, John huffs out a sharp breath, digs in his heels and bends over. He grabs Sherlock's arm and pulls. His friend's eyes flash and he bares his teeth, but when his knees are finally forced to straighten he finds his feet and pushes up. John lets go, but it's a bit too early and he suddenly finds himself with two armfuls of consulting detective. It is only by their sheer proximity that John hears Sherlock's half-snarl, half-whimper.

There is a series of sharp inhales around them, and Donovan actually snorts out a laugh. When Sherlock pushes away forcefully John finds his hands were clenched into tight, angry fists around Sherlock's coat.

He turns and meets Lestrade's eyes, and sees there that the Detective Inspector has finally caught up with the situation. To his credit, Lestrade's expression does not waver, and John is infinitely grateful when he says, "Right. Got anything?"

Sherlock rattles his deductions off with none of his usual showiness, attention fixated solely on the corpse and its immediate surroundings. Lestrade takes advantage of Sherlock's redirected focus to glare a 360 at the whole Yard, wordlessly commanding them to hold their peace. When he reaches Donovan, her face is impassive, but when he looks away her lips curl into a sneer until she catches John's gaze. Whatever expression is on his face is apparently enough to make her blanch, bitter but contrite. Lestrade's eyes move back to John's and the look they share speaks volumes. Something needs to be done before this gets out of hand, but neither of them knows what that something is.

With the killer profiled, Lestrade sends Anderson off with the forensics team to the lab, and dispatches the officers to search and capture. He offers to drive John and Sherlock home – out of earshot of the consulting detective, of course – but John turns him down with a polite smile. For a moment Lestrade looks like he might protest, or just say something, ask one of the million and one questions in his mind, but the moment passes and he just nods. John sends him a grateful look and claps him on the shoulder in return. Lestrade thanks Sherlock and bustles off to aid his investigation.

Sherlock continues to stare at the corpse.

"Cab, then? Will you be eating? Because we could stop for Vietnamese on the way home, I've a real craving for spring rolls at the moment." John shuffles up to Sherlock's side, idly examining the corpse. Sherlock hasn't looked at anyone once, not even John, since his stumble; he hasn't spoken apart from telling Lestrade who to arrest. It's been worrying John for a while now, how Sherlock just goes and outright admits who might have done it instead of running off to find out for himself. His willingness, even eagerness, to do legwork is something he prides himself in, not the least because it makes him feel superior to his brother. John looks at the corpse and comprehension hits him like a ten ton bag of wet cement.

The things that make Sherlock Sherlock are slowly dropping away, one by one. Experiments, chasing criminals, the violin – little by little, he's losing them to the deterioration of his body. He can theorize the effects of sixty-proof tequila on spilled blood, but can't test for himself because he can't steady the pipette and dispense the precise amount. He can deduce the criminal and his motive, but can't track him down for himself or wander London for proof because his joints falter and he stumbles. He can compose pieces in his head, but can't play without stumbling over the fingering or losing his grip on the bow. Up until now, however, he's always at least had the crime scenes, the deductions, the ability to bulldoze right over the Yard and trump them at their job. He's still had the bulk of The Work, the application of his genius. But now, with his dizzy spells and his struggle to focus and his difficulty initiating movements, that is slipping from him too.

Sherlock had doubted himself once, in a small inn in Dartmoor, his body betraying him as his hand shook around the glass, his mind betraying him as it made him believe in things that obviously weren't real. This scenario is much the same, and far, far worse.

"Sherlock–" John is cut off by the Sherlockian tradition of his friend whirling around and striding off without so much as a by-your-leave or see-you-later. He turns to catch up, but suddenly the ground feels too unsteady underneath half of him and oh no and please no and you damned leg, why now of all times do you choose to remind me of your psychosomatic annoyances? By the time John's recovered, Sherlock's in a cab and riding off, face turned away from the window.

John grits his teeth and, for the first time since Sherlock's return, limps, heading toward the road to catch a cab of his own. The ride home is silent, reminding John very poignantly of what is missing.

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Are you coming home anytime soon? Planning to order in Chinese. JW

Look, I'll apologize, if that's what you're after. Just come back, you daft git. JW

I'll have Lestrade make good on his missing person threat. JW

Your usual is out by the microwave. JW

Sherlock, please. JW

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John finds out Sherlock's returned when a manila envelope smacks him in the face at twenty past four in the morning, though he doesn't actually find out the time until he's stopped cussing and managed to get his bearings enough to glare at the clock at his bedside. He hadn't meant to fall asleep; all of Sherlock's unexplained disappearances have taken their toll on John's psyche and his mind has started to supply him with memories of the three long years he'd believed the detective was dead. He quickly catches up to the reality that his flatmate is sitting shamelessly at the foot of his bed, illuminated in streetlight, his gaze pointedly on the envelope and his body all wrapped up in a different suit. He hasn't come home in two days, which means he's been somewhere where he's had access to his clothing. Likely Mycroft.

Well won't Sherlock be proud of that deduction.

Having more or less woken up, John switches on his lamp and turns his own attention to the envelope on his lap, and recognizes the Bart's logo up on the corner. Medical files, then, but whose and why? A case, maybe? He opens the flap, pulls out a thickish sheaf of papers, and identifies the handwriting before the name of the actual patient. It's Dr. Shepherd's, the neuro at Bart's; he's seen it in the books he'd borrowed and the few times they'd met up. The pieces are already starting to fall into place in his sleep-muddled brain when he glances back to the top of the file and reads the patient information.

Sherlock Kingsley Vernet Holmes, it reads. Primary Diagnosis of Parkinson's Disease, pending MRI and karyotype.

That's it, then. It's real.

"I do hope you're quite satisfied," Sherlock intones, obviously trying to keep his voice steady. On anyone else he might have been convincing but this is John, he knows better, he can read the effort it takes to keep it level. He glances down the file quickly (reported initial non-rapid linear progression, likely exponential trajectory, projected time frame of a year to five, medication prescribed, further testing recommended) and doesn't even bother checking the reports from the labs or the list of drugs prescribed. Instead, he sets the file down and looks at his hands on his lap. They're shaking.

"Now that we've gotten that cleared up, perhaps you can stop looking at me as if I'll lash out at any moment," Sherlock continues, the planes of his face rigid and posture stiff. "Or as if you're just waiting for me to come apart and die."

John's head snaps up, eyes going wide and something clenching in his chest. "I don't–"

"This is me you're talking to, John. I can read a man's career history by the treads of his shoes; I'm fairly sure I can deduce the expression on your face." Sherlock's tone is as even and deliberate as ever but his eyes narrow ever so slightly and the corners of his lips tense. "Now if you will excuse me, doctor, I've had a rather trying twenty-four hours in the presence of the Omnipotent Cake Monster and I would like to rest."

The attempt at criticizing his brother falls flat. Sherlock gets up, but John gets his question out quicker. "Why didn't you bring me?"

The question is enough to halt Sherlock halfway out the door. Perhaps it's because it's the least likely question for John to have asked (so many more are waiting on his tongue but he holds them back), or because John's tone is not plaintive or accusing, simply sad. In truth it is because the question strikes a little too close to home, but Sherlock does not give that away as he turns his head from John and whispers in an unfathomable tone, "obviously."

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[unsent message – 6:02 am] It is because it is you. SH

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The next night, it is John hovering outside the door to Sherlock's room, John creeping in despite his better judgment because he realizes this is something he needs to get done. They had spent the day dancing around each other, with John puttering about the kitchen and fussing over his blog, and Sherlock sprawled out on the couch, plucking at the strings of his violin. John pushes open Sherlock's mercifully unlocked door and is confronted by the sight of the detective still fully dressed, sitting on the edge of his bed, struggling to unbutton his shirt.

They both freeze as Sherlock looks up, or rather, John does and all of Sherlock stills except his fingers trembling at his shirtfront. Before Sherlock can order John out of his room or explode or implode or whatever it is he might do, John braces himself and closes the distance between them. He gets one knee on the bed, and reaches down for the buttons to undo them himself. Sherlock's hands tense at first, but he acquiesces – or more precisely, he surrenders – and drops his hands to his lap, averting his gaze.

John undresses Sherlock slowly, carefully, methodically, hands gentle as he slips out every button, pulls off Sherlock's shoes, peels off his socks. As he works, he speaks, voice soft and (hopefully, please God) reassuring. "I still think you're brilliant, you know."

A barely perceptible hitch in Sherlock's breath tells John he's hit the nail right on the head. He's had his suspicions, increasingly so after their encounter last night, but it was still a shot in the dark since John's never been the best at deductions – and especially not when Sherlock wants to be inscrutable. But John is a doctor, and he cares for Sherlock and maybe even – "I mean, it's your mind that makes you who you are. You've always just said everything else was transport. I know right now the transport's malfunctioning and that's just – that's not good, but–" He breaks off, worrying his lower lip between his teeth as he carefully sets down Sherlock's shoes at the foot of the bed. When he looks up, Sherlock is staring at him with the most vulnerable expression he's ever seen. It makes him look like a lost little boy, and it breaks John's heart.

"I don't want this to be happening any more than you," he finishes quietly. He gets up and makes to perch on the bed beside Sherlock, but before he can so much as bend his knees the wind gets knocked out of him slightly as Sherlock shifts forward and shoves his face into John's gray jumper. His spindly arms come to wind around John's hips, and it's a while before John realizes the shaking of his shoulders isn't from the PD.

"I am frightened," comes Sherlock's muffled voice, and John wishes more than anything that he can reply something other than, "I know."

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When Sherlock had first come back from the dead, John had stormed out of his flat and returned two days later to Sherlock in his bed. John had left him there, just let him say there, while he'd kipped on his own couch. But the fourth day after that found John creeping into his own room and slipping under his own covers and running his fingers over every surface of Sherlock he could reach, over and over for hours on end, until he'd managed to start convincing himself that Sherlock was really there. His friend had had his eyes open the whole while, but had kept them averted, preferring to watch the rustle of the sheets.

Now, two years later, John finds himself tucked into Sherlock's bed in his day clothes, waking up from a nightmare, gasping and sweating and shaking. It's not of Afghanistan and it's not of Sherlock dead – or at least, not in the way he used to dream. He has vague snatches of needles spinning on floors and Sherlock falling down a flight of stairs and very, very bad things happening, and it has him reaching out, seconds away from calling Sherlock's name. Before he can articulate the scream, though, a gentle hand smoothes the rumpled cloth at the small of his back, rubbing small, reassuring circles. He turns and finds Sherlock looking up at him, scrutinizing and contrite. John gives Sherlock a tiny smile that seems to satiate him, because his flatmate sinks back onto the pillows without a word. After a few moments, John follows.

The room is dark, the streetlight filtering in and casting odd surfaces – the crests of the wrinkles on the sheets, the shoes at the foot of the bed, the femur on the bedside table – into sharp relief. Sherlock's prone form is outlined in faint light and cloth. John's panic peters out, leaving him a bit shamefaced and nervous. But there is a barely-audible sigh, and the body on the bed shifts to leave a little more room on the left side. John wiggles forward, curling a little more into Sherlock and his space. Then careful hands are tucking the blanket back around his ribs, and John can feel their forced steadiness through his shirt.

He lifts a hand, but instead of restlessly roving Sherlock's skin as he had two years before, he simply brushes his knuckles down Sherlock's face once, from temple to jawline. He braces himself for the flinch, for the tension, but it doesn't come. Instead, a slender hand reaches up to grip his own, uncertainly, loosely, drawing it down to a spot where he can feel a heart thudding like a rabbit's. (Years ago, at a pool – I will burn the heart out of you, and there is a three-year hole of nothingness in John's life to prove just what that statement had meant.) It's only the work of a few moments, barely any kinetic energy spent, the motion of a dozen muscles or less, and yet between them it says everything.

Sherlock's impossibly blue (or green or gray or god, John doesn't know but he doesn't really care, what matters is they're Sherlock's) eyes hold John's the entire time, rendered nearly colorless by the hall light. They simply look at each other, quiet and still but for their breathing. John's hand is sandwiched between the pulse from Sherlock's own and the thud of his heart. He is the first to fall back asleep.

When he wakes to the gray light of dawn, Sherlock is gone, but the spot beside him is still warm. John curls up into it gratefully and closes his eyes. From the living room comes the sound of a stilted violin.

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I trust you see my point now, little brother? MH

Mummy always said gloating was unbecoming, Mycroft. Your smug grin makes your cheeks look fat. SH

Petty insults get you nowhere, Sherlock. MH

No, but facts do. SH

I'd no idea sentiment would make you so childish. MH

But I've always known being right makes you a pompous git. SH

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The next time Sherlock goes to the hospital, John goes with him.

He knows Sherlock needs further tests but he doesn't know when or what. He doesn't ask, though; ever since that night, John knows to let Sherlock come to this in his own time, let him come to terms with his body. It is therefore a bit of a surprise when Sherlock comes out for breakfast fully dressed, three days afterward. He loiters in the kitchen a bit, then ambles over to where John is eating at the table, file in hand.

John looks up from the paper and his tea, and waits for the words, patient and silent.

"Dr. Shepherd emailed. There are cranial tests I'm to take and he'd like to speak with you. Apparently my flatmate ought to be aware of the full extent of my condition." Sherlock fiddles with the file and doesn't look at John. The last bit feels a little lacking, but Sherlock doesn't offer anything more.

John sets down his tea. "Does Dr. Shepherd know your flatmate's a doctor?"

"Yes, but neuro isn't exactly your specialty. Though I suppose you'd better come along, anyway. At the very least you'll get the gist of things." Sherlock's stab at a supercilious tone would make John laugh if it isn't so paltry.

John folds the paper and gets up to change. To his surprise, Sherlock beats him to the breakfast things, snatching away his plate and cup before John can so much as get his bearings. He wonders if this is an apology or an escape, but he doesn't complain. Sherlock is going to the doctor and Sherlock is letting him in. As far as John's concerned, that's enough for now.

Sherlock hails a cab with his usual pomp, and they ride off to Bart's in almost complete silence. It is only broken once, when halfway through the ride John turns to Sherlock and reaches out a hand to his.

"It's all right to need me," he says gently. Sherlock keeps staring out the window, but his fingers momentarily close over John's and that's all the reply John needs.

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Dr. Shepherd is pleased and unsurprised to see John.

"Should have guessed," he says as they settle in his office, John and Sherlock in plastic seats on one side of the desk and Shepherd in a tall desk chair on the other. "All those consults and then Mr. Holmes here coming in, asking to be tested, saying he's got a doctor for a flatmate. Admittedly I didn't recognize your name until he said it, Dr. Watson, so you'll have to forgive me. I was a big fan of the blog, you know, when it was around." He smiles, genial and professional. John waits for Sherlock to stiffen, tense, but Sherlock is merely having an idle staring contest with the skull on Dr. Shepherd's desk.

"Still, took a while, didn't it? Gap of, say, five, six months? Though I suppose it's an elimination process, given how hard PD is to diagnose. Tricky symptoms, easily construed as other diseases," Dr. Shepherd continues, taking a file from one of his drawers and flipping it open. There it is, in official, unforgiving hospital print: Sherlock's diagnosis and the accompanying courses of actions. From across the desk, reading upside-down, John can pick out the various medicines, which symptoms they're supposed to be targeting. Even though he's done the research himself, the fact that all this now formally and actually applies to Sherlock hits like a blow to the gut: it makes the bile rise in John's throat and makes it feel like all his breath's been knocked right out of him. Thankfully, Dr. Shepherd seems to have dealt with situations like these plenty of times (well of course he has, Watson, John thinks, he's a neurological specialist, he probably diagnoses degenerative diseases everyday) because he slips into full doctor mode, splaying the file out on the desk.

"The patient is Mr. Sherlock Holmes, come in five days ago for a consult and check up. Symptoms include but are not limited to: tremors, initially intermittent and now more regular, in extremities, most notably hands, arms and knees; arrhythmic twitching of muscles in face, arms and legs; difficulty focusing vision resulting rapid, frequent blinking; developing bradykinesia, a stiffness of joints that renders initiation of movement problematic; increasing frequency of dizzy spells; and more recently, recurring stumbling or faltering while in active motion." As he speaks, Shepherd lays a pamphlet for Parkinson's Disease on his desk and encircles the various symptoms he's enumerated in red pen. "My diagnosis, after the initial tests, is Idiopathic Parkinson's Disease, sometimes referred to as Primary Parkinsonism. It is a neuro-degenerative disease characterized by progressive loss of muscle control that occurs when the brain slowly stops being able to release dopamine to signal the nervous system to stimulate the muscles into motion. The communication between the brain's substantia nigra and corpus striatum – the two parts controlling smooth movement – is interrupted because of the degeneration of dopamine-producing cells in the substatia nigra. The brain starts to lose control over the body, hence the involuntary tremors and other symptoms. Is this clear so far?"

"Nothing I haven't heard before, Dr. Shepherd," John replies easily, reading down the symptoms list and the following paragraphs on what causes them and what to do about it. Shepherd huffs out a tiny chuckle; this is obviously easier than the other times he's had to explain this to patients and their families and friends. Not much explaining to do when your patient is a genius and his friend is a doctor who's already done extensive research on the subject.

"I administered the primary physical examinations upon first appointment, principally checking reflexes and movement control. During these tests, we generally look out for loss of fine motor control, involuntarily trembling limbs, frequent closing of eyes or deliberate blinking, and hesitation before initiating motion. Mr. Holmes has also informed me that he has chemistry for a hobby, and that he is no longer able to perform the experiments requiring finesse and precision, particularly when dispensing liquids from pipettes or slicing minute samples." Shepherd slides over a few pages from the file. John notices that he does not mention Sherlock's detective work. Sherlock idly taps his fingers on the arms of his chair. "I asked that he come in today for an MRI, possibly a CT scan, and a blood sampling for karyotyping. It's possible this is genetic; up to three percent of PD cases are."

"Have you checked his–?"

"Mycroft is not aware of anything in our family history," Sherlock interrupts. Something about the way he says it tells John this isn't a reassurance that there has never been PD in his family, but rather, a statement that there could be and they just didn't know about it. Which troubles John quite a bit. Mycroft's supposed to know everything.

"Given the circumstances, I feel a karyotype might be beneficial. At the very least, it will not be a loss; it is simply just another test, anyway." Shepherd lays out a few more papers and John finds himself a bit overwhelmed. He hasn't dealt with anything this complicated since his intern days; at the clinic it doesn't take much to diagnose a cold or chicken pox, and on the battlefield there's no paperwork for being elbow-deep in a man's guts. Shepherd smiles reassuringly and shuffles the papers together. "For treatment, well. It'll depend of course on what the tests show, but generally we'll start him on Sinemet – a form of medication that contains levodopa, a chemical normally used by the brain to create dopamine. It also contains carbidopa, a chemical to prevent dopamine formation outside of the brain. The Sinemet will likely be used in tandem with Catechol-o-methyl transferase, or COMT, inhibitors that will prevent the body from breaking down the induced dopamine. Then there's pramipexole, tolcapone and of course, physiotherapy."

Dr. Shepherd pauses. John feels a bit dazed. Even Sherlock looks a little rattled. Shepherd looks from John to Sherlock and smiles reassuringly. "It'll be fine. I'll explain everything in detail and in layman's terms – if you'll forgive me – when the tests come back. Don't worry. I'll walk the both of you through every step of the prognosis and the stages of medication. For now, though, do either of you have any questions?"

John, slightly occupied with reading through the transcript of the physical examination, hums a vague "no." Sherlock merely shakes his head. Dr. Shepherd goes "all right then," and presses the buzzer on his desk to summon his assistant.

"Mr. Holmes, this is Dr. Stevens. She'll walk you through the MRI procedure. If you will follow her please."

Sherlock flicks his eyes over the slight woman and John can practically see the gears crunching in his mind as he reads her history, her career, her breakfast. He braces himself for the onslaught but is surprised when Sherlock merely stands, narrows his eyes, and sweeps out of the office area. John rises to follow but Dr. Shepherd clears his throat.

"If you don't mind, Dr. Watson, I'd like to speak with you privately." There's a bit of a grim look on his expression that makes John's heart forget to beat for a moment. He sits back down in trepidation.

"Just Mr. Watson or John will do, Dr. Shepherd. I'm not exactly here in a professional capacity." John smiles tightly, settling into the uncomfortable chair as best as he can manage.

"But I'm speaking to you in a professional capacity." Dr. Shepherd's face is grim as he takes a few papers from the thin sheaf of Sherlock's documents and spreads them out. "You're a doctor. Granted, not a neurologist, but I know you've been doing the research. And it does remain that you, like me, have taken the Hippocratic Oath. Now, I have asked Mr. Holmes every standard question for diagnosis, and both he and his brother have managed to make me feel like a right idiot despite my medical degree and specialization." He and John chuckle good-naturedly before Shepherd exhales a humorless smile and goes on. "But I haven't been a neuro for ten years for nothing. There are things he isn't telling me, or things he's choosing to leave out, and as his doctor I need to know."

No, I'm his doctor, John thinks, irrational and for a moment angry. But his only outward sign of irritation is to press his lips together and breathe out a tiny sigh. He knows all too well what it's like to have patients who don't tell you the whole story, from his years of practice before and after the war. And it would be just like Sherlock to dispense only what he thinks is relevant to the current diagnosis; he's never been much for 'anything else you'd like to tell me?'

"Fine." John gives a barely perceptible nod of his head and Dr. Shepherd smiles in relief. He props his elbows up on his table and takes down a notebook; John's shoulders slump and he rubs the bridge of his nose. "What do you need to know?"

xxxxxxxxxx

They talk for the three hours it takes to subject Sherlock to an MRI, CT scan, blood test, urinalysis and x-ray. By the time the consulting detective returns, John is exhausted by the number of questions he's had to answer. The symptoms showed up roughly a year ago, it was when he dropped his violin bow, I was consulting for him when he wouldn't, no I didn't want to bring him in, I couldn't even if I tried, it took him maybe half a year before he even began to resign himself to the possibility, and so many other things Sherlock had left unsaid. Shepherd has, of course, with the diplomacy of a professional doctor, revealed nothing of what Sherlock had told him, other than to comment on the least personal of things – mostly those that related to John – and say Sherlock hadn't mentioned them in their initial consult.

When Sherlock strides in it's clear to John that he's been terrorizing the hospital staff again, faulting the nurses for tiny errors or deviations in procedures, deducing their personal failures. Dr. Stevens looks particularly irate; her smile when she leaves can barely be called polite. Sherlock's lips are pulled up in grim satisfaction, and he settles himself into the seat next to John with enough pomp to rival the Queen.

"I've received notice of the results of your test, Mr. Holmes," Dr. Shepherd says, all civility and politesse. "But I'd much prefer to wait until the karyotype results before I discuss them with you. Unless you'd object, of course, I believe we're done for the day. Dr. Watson, any questions?"

John starts from where he'd been slouched in the chair, fingers kneading the bone between his eyes in exhaustion. "What? Ah – well, how long until the karyotype comes out?" Beside him, Sherlock makes a growling noise; the man obviously just wants to leave.

"Three days maximum. I'll email or call when they're here." Dr. Shepherd tucks Sherlock's papers back into their folder and hands over a pamphlet for PD (to John, not to Sherlock). "Thank you very much for coming in. I'll see you both again soon."

"And hopefully by then you won't still be sleeping with your intern," Sherlock deadpans. He smiles tightly, that taut pull of cheeks that stretches his lips thin, and whirls off. Dr. Shepherd looks appalled. John heaves a sigh.

"Right. Sorry about that." He flaps the pamphlet and forces a smile of his own. "Well – thanks." He wonders if he ought to say something else, but then can't think of what to say, and both he and Dr. Shepherd are feeling rather uncomfortable anyway. So he nods and heads out the door after Sherlock.

When he gets downstairs he is mildly surprised to find Sherlock's waited for him, holding a cab outside the hospital lobby. Admittedly he'd half-expected Sherlock to just go off on his own as usual; he'd certainly been in the mood for it. With a derisive glance at John, Sherlock gets into the cab, sliding into his designated side of the seat. For a moment John considers not joining him, considers taking off for a walk on his own, because he desperately needs time alone to collect himself and come to terms with the mess that is his – no, their life.

Well, Sherlock's disappeared on him enough times, and John really needs to get his grips.

As he approaches the cab, Sherlock's shoulders slump down a little, as if he'd been holding them in tension, waiting for John to follow. The furrow appears on his brow when John places a hand gently on the cab door and shakes his head.

"You go on ahead," he says, smiling lightly at his friend. "I'll be home in a bit. I just – I need some air. A walk." He wants to explain but how would he do it? Sherlock understands, anyway, or John hopes he does, because after a pause he nods and turns away.

"221 Baker Street," John tells the cabbie, softly, and then he shuts the door. The cab heads off, and John begins to walk in the opposite direction. It's just their address, it's something he's told dozens of cabbies all these years he's lived with Sherlock, it's nothing new and yet it makes John so inexplicably sad. It chokes his throat.

Which it shouldn't. Baker Street is home.

xxxxxxxxxx

John wanders the streets of the city, hands tucked into his jacket pockets and chin ducked down to his chest. He has a feeling the security cameras are all following him again but he doesn't even look. The entirety of the consult is whirling around on repeat in his head, but there is one line he keeps irrationally fixating on and it's driving him mad.

There are things he isn't telling me, or things he's choosing to leave out, and as his doctor I need to know.

I'm Sherlock's doctor, he thinks again, gritting his teeth. He knows it's unreasonable and absurd – he's not a neuro, he's nowhere near the level of expertise required to deal with this – but the fact remains that he is Sherlock's doctor. He should be the one treating Sherlock, the one gently cupping his chin as he flicks the penlight before his eyes, the one patiently waiting as Sherlock tries to handle precision equipment and read a letter chart. He should be the one taking care of him. John grumbles and kicks an empty can against the brickwork of a nearby wall. What's he managed to do? Some paltry research, plenty of ignoring the circumstance, and that one time he'd yelled at Sherlock for oh bloody bleeding hell he's left Sherlock on his own.

John whirls around and flings his arm out to catch the first cab that comes hurtling down the street.

He's only left Sherlock alone and unsupervised once since their fight, and that had been when Sherlock had abruptly left the crime scene to finally be properly diagnosed. He's fairly sure that since Sherlock had been with Mycroft, there wasn't any danger of his ingesting any illegal substances. Today, however, John can't be quite sure, and after that last time he doesn't want to be taking any chances.

But as John sticks his hand out for a cab he feels a sickening stab of guilt that makes the bile rise in his throat. Has he so little faith in Sherlock that he'd think the moment the detective is left alone, he'll make a mad dash for a drug?

Somehow, John doesn't really have an answer. The Parkinson's Disease pamphlet flutters to the ground by his feet and he doesn't notice.

A cab pulls up and he gets in mechanically. It rolls off and John stares out the window, looking at London pass him by without really seeing it. He left Sherlock what, an hour ago? That's plenty of time. But he wouldn't. Not after the last time. Would he?

xxxxxxxxxx

When John gets back to the flat, Sherlock is sitting on the couch, elbows on his knees, fingers steepled over his chin. He doesn't look up as John bursts through the door, doesn't react beyond a slight shift of knee and a nervous flick of tongue. His gaze is trained on something in front of him and John follows his line of sight. It sets him on the edge immediately.

The coffee table is cleared, the papers and books that had been haphazardly stacked on it now scattered over the floor behind. It only contains one lone cup of tea, likely cold, and the tiny white packet John had palmed off Sherlock all those months ago.

"What is that doing here?" John bites out the question before he so much as assesses the situation before him; in hindsight, he should have looked first and asked questions later. But he's just rocketed through more emotions that he'd thought possible in the last ten minutes – he needs to vent.

"It isn't used, John," Sherlock intones, hardly glancing up. His knee starts to twitch again, and John can see where he digs his elbow in ever so slightly to try and get it to stop. And then he actually has the gall to lean back and roll his eyes. "Have a little more faith in me than that."

His tone is so sardonic it jacks John's temper right up. "Well I'm sorry for asking," John hisses, stomping inside and slamming the door shut. "It's just that there was this one time where you shut yourself away and I'd no idea what you were doing, and then I got a text from your goddamn brother telling me that hello, someone saw Sherlock buying drugs, mind if you take care of it? And sod it if I don't panic, nearly break my neck going down the stairs and yeah, there you are with – with that on you–" and here John flings his arm out, gesturing violently toward that seemingly innocuous packet of white powder – "and you know what I said then, Sherlock. You know what I said and I don't want to say it again." He clicks his jaw shut, heaves in a breath.

Sherlock's still staring at the packet.

John starts forward, ready to jerk Sherlock's head up to look at him if necessary, but then he catches sight of the expression on Sherlock's face and it floors him. (Because three years ago, the last words he'd ever said to Sherlock in person before that utterly horrible moment, you machine, and the year before that when he'd told Sherlock that he'd had a row with a machine, it sat there and I shouted abuse at it.) Sherlock swallows thickly and still does not look up as he says, deliberate and even, "it isn't pleasant, is it?"

John stays rock still and very quiet.

Sherlock huffs out a bitter laugh, dropping his hands between his knees. His eyes flick up toward John, filled with an anger that is only directed toward himself. "It's not very pleasant having to watch me go to pieces and be able to do nothing."

John feels like he's just been punched in the gut.

No, no it isn't pleasant, not at all, in fact it's utterly unbearable, but that's not all Sherlock's trying to say. Sherlock would be proud, actually, if he sees now how quickly John picks up, or maybe it's just because John was thinking about it in the cab over. This is the first time in one and three quarters of a year that the topic of Sherlock's jump off the Bart's roof and their subsequent three year separation has come up, and the first time ever that Sherlock has spoken, however indirectly, of just what those three years were really like for him. John knows by now that Sherlock had tried not to watch him, during that time, had tried to stay away, to detach, because knowing would only have made things that much harder. He also knows that Sherlock hadn't succeeded, and on that night (three months after The Fall) he'd gotten himself piss drunk enough to puke all over the bathroom floor, the Sherlock he'd seen in the doorway really hadn't been a hallucination. All those years and Sherlock running all over three continents, all while knowing John was slowly wasting away back in London and he could not do anything.

The ache blooms in John's chest, cold and heavy, and he willingly surrenders as it drags him to his knees beside a man that yes, goddamnit, he loves.

"God, no," he rasps, hands stilling Sherlock's leg as they cup over his knees. "It's not. No."

Sherlock drops his head to his hands, teeth bared in a grimace. "I can't–" His voice breaks and so does John's heart. "I need–"

"No." They've been using that word a lot, John realizes, him in particular. "I mean – no, Sherlock, you don't need – you can't–" He breaks off in a shuddering gasp that is decidedly not a dry sob. "You have me. Please. Just – just – you don't need that anymore, you – you have me."

Sherlock lifts his head to hover above his hands, tilts his head to catch John's wavering gaze with those impossibly blue eyes. His lips part slightly; his eyes tighten in abjection. John wonders if this is what Sherlock had looked like, all those long years. Watching, always only watching.

"I can do something." John's feeling rather desperate, too. "Something, anything you need – anything at all. I'm here, Sherlock. You have me. I know all those years, you were fighting on your own, but you're – you're not anymore, you know. You have me."

Sherlock's eyes are devastated. John reaches up, past those trembling arms, and cups his face. He draws it gently up and forward and, twisting a little awkwardly, pushes up on his knees until they're almost level. Sherlock does nothing to stop him.

"Let me," John whispers. Sherlock's eyes are still caught on his in a gaze that is heart-stopping in its intensity. He snags his lower lip between his teeth – and nods.

And then oh, oh, they are kissing, just a soft press of lips on lips, but it is a kiss and it is everything John hadn't known he'd wanted. Sherlock is pliant above him, uncertain, but when John pulls away for the briefest moment Sherlock follows him down. He tumbles ungracefully from the couch, John pulls him down, and an awkward struggle has John on his backside, knees bent low, with Sherlock straddling his lap and kissing him, certain now, taking and not just receiving. One of John's hands is tangled in Sherlock's curls and the other is grasping the lapel of his shirt; John doesn't know where Sherlock's hands are until they're tugging his undershirt (when had Sherlock undone all his buttons?) out of his jeans.

"What–?" John barely gets the word out before Sherlock's lips are once again smothering his. This next kiss is salty and damp, but with the way they're fumbling at each other and the way they both feel, John can't tell which one of them is crying.

"Let me." Sherlock echoes John's words back to him in a ragged voice. He crushes their mouths back together and rucks John's upper body clothing to his ribs, hands skimming the newly-exposed skin.

"All right," John gets out between kisses. His own hands are sliding over Sherlock's face, down his arms, then falling back to support himself as Sherlock leans him back, moving down to ravage his neck. "All right."

Sherlock surges back up and their kisses turn hard-edged and desperate. There is the slide of teeth on lip, teeth on teeth, and John thinks he tastes the copper tang of blood. Their hips rock against each others'. Sherlock shifts them so that John's leaning against the couch, their bodies sandwiched in the tight space between couch and coffee table. The cup gets knocked over in the process. Then John loses track of most other things apart from Sherlock's mouth on his and the things that tongue is doing until he hears a tinny schip and a pressure around his hips is relieved. His noise of protest gets swallowed by Sherlock, and he reluctantly pulls away to make himself heard.

"Don't–" He's cut off again in the same manner and this time he jerks his head forcefully to the side, hands coming up to still both of Sherlock's where they're clenched above his crotch. "Sherlock, don't."

"Let me," Sherlock demands, raw and wrecked. The tone shoots right down John's spine, bypassing his rational mind entirely in favor of another traitorous part of his anatomy. Christ, how can he want it, at a time like this? Has he gone utterly starkers? He opens his mouth to protest a little more vehemently but chokes on the words as Sherlock shoves a hand down his pants.

Oh god – those fingers – how the hell – god, yes – shouldn't be – more, fuck, morenot good, not – good – Sherlock – Sherlock – "Sherlock–"

"Please," Sherlock whispers into the crook of his neck, right at the top of his clavicle. His hand tightens, speeds up, dragging slightly roughened skin over John's cock and this is wrong, isn't it, this shouldn't be happening, but god if that doesn't stop John from scrabbling at the floor boards and crying out Sherlock's name as he comes.

It isn't until Sherlock slumps against him, boneless and positively gasping for breath, that John notices Sherlock's trousers have been messily shoved down to the tops of his thighs and he has a hand down his own pants. "John," Sherlock rasps, then swallows audibly, withdrawing a hand covered in sticky, white cum. He slams it onto the couch by John's head as he braces himself, trying to regain even a little of his composure. "John."

John brings his arms up, winds them around Sherlock's waist, clutches the back of his shirt tight. Sweat drips off Sherlock's hair and face as he hovers over John, knees awkwardly bent, body uncomfortably folded. He draws back a little, eyes skittering over John's face. "You–"

"Shhh." John offers Sherlock a tiny smile and slides a hand up and around to splay over Sherlock's rabbit-fast beating heart. (Moriarty that night: I will burn the heart out of you. They know now. Oh, how they know.) "I know."

And then they are just holding each other, sprawled out on the floor, spilled tea seeping into the cuff of John's jeans, something on or in the couch digging into his left shoulder, right under the scar, but Lord knows he's had worse pain and that right now, a little discomfort is nothing compared to what Sherlock's feeling. So John simply smoothes down Sherlock's hair and tightens his arms around him, and they cry – Sherlock for all that he is losing, and John for all that he cannot do.

The heroin packet lies on the table, forgotten.

xxxxxxxxxx

Triple homicide, Lauriston Gdns. All strangulation but no fingerprints, not even DNA. GL

Victims have no discernable link. GL

Donovan's on vacation. GL

xxxxxxxxxx

The medicines pile up in the bathroom, next to John's razor and their shared toothpaste. John stares at their labels each morning as he brushes his teeth. Sinemet. Mirapex. Tasmar. Azilect. Cogentin. Provigil. The Prozac in particular makes John's jaw clench. It's unopened; the tape is still on the box and everything. But the fact that it's there, however precautionary, stings. Sherlock isn't depressed. Sherlock is still as vibrant and brilliant and fascinating as ever. Sherlock is stillSherlock and this disease is not going to change that.

John is rather determined on that point.

Sherlock's not too bad yet that he'll need physiotherapy, but he does move around the flat more often than usual. He tries to put it down as restlessness, and probably on a large part it is (he hasn't been taking cases and it hurts to think why), but John also knows Sherlock's trying to keep moving, work out the stiffness of his joints and keep his equilibrium in check. John's taken half shifts at the clinic so he can keep an eye on Sherlock and so he can just generally reassure himself that the consulting detective is all right.

At first Sherlock is resentful and stroppy, but one afternoon John comes out of the bathroom to find Sherlock struggling to make tea (two cups, he remembers now, one with two sugars and the barest dash of milk), grip slipping over the lid of the tea canister. He drops the jar onto the kitchen counter with a choked snarl of frustration, clenching and loosening his trembling fists. After only the slightest of hesitations, John sidles up behind Sherlock and winds his arms around his waist, caging his arms to his body. He presses his face between Sherlock's shoulder blades and rubs slow, reassuring circles into his skin.

Sherlock hasn't been complaining as much after that.

So much is changing about the dynamic of their relationship, and so much isn't. Sherlock still leaves things lying half everywhere and John still has to be the one to buy the groceries. Sherlock still makes noise around the flat at ungodly hours in the morning and John still has to remind Sherlock to eat. Sherlock still hogs the bathroom in the mornings when all John wants to do is take a piss and brush his teeth. But Sherlock makes the tea now, sometimes, and sits through crap telly with John, and once brings him home a miniature plastic TARDIS autographed by David Tennant that he'd apparently been given for free because the second assistant director owed him for exonerating her father. As far as relationships go, in John's opinion, it's pretty good.

Sometimes, on the quiet days when Sherlock has his head in John's lap and John's carding his fingers through his curls, slow and gentle, John watches the tremors in Sherlock's limbs and feels his throat tighten a little. Times like these almost always end up with Sherlock falling asleep and John slowly losing the feeling in his toes because he doesn't want to ask Sherlock to get up; it means having to watch him struggle to move, joints stiff and movements ungainly. It is inevitable, of course, that Sherlock will get up, but John tries to delay it as long as possible.

The little egg timer always buzzes, always kills their little bubble, and with lips pursed tight Sherlock laboriously sits up while John fetches whatever pill he has to take. If there's one form of help Sherlock's never complained about, it's when John wraps both hands around his to steady the glass of water and lift it to his lips.

Sherlock's hand never shakes then.

xxxxxxxxxx

Quadruple homicide now. Don't fancy the statistics much. GL

I'll bring the squad car over, so help me. GL

[unsent message – 3:09 am] I can't. SH

xxxxxxxxxx

"Potential link's been discovered. Seems they all visited the same coffee shop at some point during the day. They all had some sort of business in that area – a house, an office, a yoga class. This latest one has a daughter living in that area. She was the one who reported her mum missing; seems the woman – Margaret Lannister, 48 – was supposed to visit her that day. Likely she stopped for a coffee on the way over." Lestrade briefs them outside the house of the girl, Elizabeth Lannister. He looks plenty worse for the wear, with dark bags under his eyes and what looks like new wrinkles in his skin, but he's on high alert and doing his fucking job because he has to. "Body was found three blocks away from the coffee shop, five blocks from the flat. Strangulation, no finger prints or anything we can strip for DNA. Murder weapon's been IDed as nylon string – thin, light but strong. All the victims had some sort of product from the shop near their bodies, were in their forties or older, had families. That's all I can tell you."

John hovers by Lestrade and listens intently, but keeps an eye out for Sherlock, who's peering over the house fence to check the ground. A serial killer, then, likely (oh, it's Christmas! Sherlock had said that very first night they'd met, and serial killers are always good, you just have to wait for them to make a mistake). Idly John wonders what the mistake is, this time, and if Sherlock will spot it. Then he feels the whiplash of self-directed anger. Of course Sherlock will spot it. He's Sherlock.

"Do you have the time of her visit?" Sherlock asks, eyeing the apartment complex up and down. Elizabeth Lannister lives on the second floor, sharing a tiny flat with her best friend from university. She's hovering in the doorway now, university age, pretty in a quiet way, her purple jumper just a little too big for her skinny frame.

"Three in the afternoon," she's quick to answer, in a voice raw from crying. "Please Mr. Holmes, you–"

"What time was she found?" Sherlock cuts through, turning to Lestrade. Donovan, as promised, is on vacation, but Anderson is here. He and the rest of the Yard have been tiptoeing around Sherlock, and John gets the feeling they've all had some sort of order from Lestrade to shut up and buck up. If the sidelong glances are anything to go by, however, they're all still very curious about what happened that last time.

At the back of his mind, John wonders if their betting pool is still running, and if so, how last time had affected it.

"Thirteen minutes past five. Miss Lannister found her when she walked past the side alley the body had been left in. There was a bit of a crowd gathered, the usual hysteria surrounding the discovery of–" Lestrade breaks off with a cough as he catches the distraught look on Elizabeth's face. Sherlock visibly rolls his eyes.

"The other victims. How long after their deaths were they found?" He's a little snippy that he won't get to see the body (it's at the morgue and they're at the crime scene, price to pay for coming into the investigation so late). John, having wandered around a bit examining their surroundings, lays his fingertips lightly on the small of Sherlock's back in a wordless request for him to relax. It doesn't work, and John didn't expect it to, really, but it's still nice to do so all the same. If Lestrade notices, he doesn't comment.

"Six hours at least." The furrow appears on Lestrade's brow, the one that always comes out when he's finally caught the end of Sherlock's thought tether and is starting to work his way up. "Lot longer than this last victim."

"Does your mother visit often?" Sherlock directs the next question back to Elizabeth.

"Yeah, but usually around lunch. Stays for a few hours, leaves. She was late that day 'cause she wanted to catch this special on the telly."

Sherlock pauses, looking at Elizabeth intently, who shrinks a little under his gaze (and John can't blame her; Sherlock's stare can be really unnerving). Then a smirk breaks over his lips; the tangents are racing in his mind. He's figuring it out. "Ah, so that was his mistake."

"His?" John asks, frowning up at Sherlock.

"Statistically more likely," Sherlock replies dismissively. He begins to pace, movements only slightly halting, curls dancing madly as he whirls about. "How long have you been living here?"

"About a year." She worries her lower lip between her teeth. John has to look away for a moment because that sort of information ought to be something Sherlock can easily deduce; for him to ask means his focus is out of sorts again today. Not good. Lestrade looks appropriately surprised but tactfully refrains from commenting. Anderson, most unfortunately, chooses that moment to break whatever beautiful silence he'd been holding.

"Couldn't figure that out for yourself, freak?" he sneers, tipping his head back so he can look down his nose at Sherlock. John's hackles rise; Lestrade shoots Anderson a warning glance. Sherlock's face tightens visibly, and his lip curls in a snarl. Anderson doesn't seem to realize how close to home his question hits.

"It isn't as if you could, either," John spits out, then blinks in surprise at himself. Normally he's the appeaser, the mediating presence that tries to water down the biting remarks from either side. Lestrade smothers a grin, and Anderson looks affronted, but Sherlock glances down at John and his expression mixes gratitude with bitterness.

"How long has your mother been visiting you?" Sherlock asks, bringing his attention back to Elizabeth, who's been watching this exchange perplexedly.

"Eight months. Told her not to come see me 'til I'd gotten settled in, see." She twists her pale blonde hair between her fingers, so unbearably young to be answering to a police investigation.

"So the killer's been around for less than eight months." When everyone around him looks at him with confused expression, Sherlock heaves a great sigh and John can practically hear the really, how do all of you manage to function on a daily basis, you're all so dull going through his head. "He's familiar with the victims, because he plans his attacks keeping in mind that they won't be discovered until later. But he's not familiar enough to know them intimately. Likely Mrs. Lannister passes by the coffee shop on her way home after her visit to her daughter – if she comes at around lunch, then leaving mid-afternoon is a good time for a coffee or a snack. But she's late that day, so she buys her coffee before her visit to her daughter, not after. But the murderer thinks it's after, doesn't know she's late – they're familiar with each other that he knows her afternoon stop for coffee, but not friendly enough that she'd chat about her day and tell him she's just on her way." He whips out his phone, though to check what, John doesn't know. "Check the coffee shop for male employees who've been hired within the last say four, five months, particularly those who've called in sick since the time the victim was discovered, or missed their – no, on second thought, just check who works the afternoon shift. No older than late thirties, staff or counter worker, not manager or higher."

Lestrade sighs in relief and rubs the bridge of his nose. "You heard the man," he says loudly, craning his neck to look over his shoulder at his team. "Let's go."

xxxxxxxxxx

The killer ends up being the janitor of the coffee shop, a thirty-five year old man with a nasty scar on his upper arm from the war, whose mother had raped him and walked out on their family when he was a teenager. They're currently chasing him down dark alleys; he'd run off right before the police could get him. Sherlock hurtles around corners while John puffs along behind him, and he's concentrating so hard on not thundering into a wall that it's not until there's a tinny clang behind him that he realizes Sherlock's fallen behind. He pauses, makes an unsteady turn, and discovers that Sherlock hasn't just fallen behind – he'd fallen over completely. The man is on one knee next to a skip (likely what had made the metallic noise), one hand on the rusty metal face and the other on a death grip round his patella.

"Sherlock–"

"Go." Sherlock's curls and the dim lighting from the dying afternoon light obscure his expression. His arm shakes where it's braced against the skip. There's a dark undertone to his voice that sends a frisson of not good, not good down John's spine.

"But–"

"He's getting away, John. Go." Sherlock's tone brooks no argument. John hesitates a second more. Sherlock needs help – bradykinesia and disrupted equilibrium – but all the effort he's put into this case will be for naught if they lose the killer. And Sherlock will not forgive John if he stays. So with an almighty effort, John wrenches his gaze away from Sherlock and continues their pursuit.

He catches up with the killer three blocks later, knocking him to the ground with a well-executed tackle and straddling his back (no mean feat with those flailing limbs and a desperation that practically has the man foaming at the mouth). Lestrade and some other officers catch up a few minutes later. The Detective Inspector waits until they've handcuffed the killer and are leading him to the squad car before he asks the all-important question.

"Where's Sherlock?"

John, who's been dusting himself off and checking for any scrapes, blinks and pats his pockets, suddenly worried. "You didn't pass him on your way here?"

"No." Lestrade barely gets the word out before John's making a mad dash for the main road, flinging a hand out for a cab. He doesn't know why he's panicking, only that he is, and gut instinct is telling him something is very wrong. As the cab speeds off he whips out his phone, sending frantic texts. No replies. He switches to calls, ringer buzzing in his ear. Redial, over and over again. Sherlock does not pick up.

xxxxxxxxxx

Sherlock, where are you? JW

Culprit's been taken into custody. Chinese or Indian? JW

Don't you do this to me. JW

Sherlock.

Please tell me you're all right. JW

Please.

xxxxxxxxxx

John bursts into the flat just as a drizzle starts. He takes the steps two at a time, tripping midway, heart thudding. If someone were to ask him afterward why he was no frightened, he wouldn't be able to say. He just is. He skitters onto the landing, nearly face-plants into the door, and yanks it open.

Oh.

Oh.

Oh Jesus, no.

God, no.

No.

"Sherlock!"

The harsh Afghanistan sand under the starburst of a sniper shot wound had nothing on this.

Saying his name like the last time he'd died (you great big colossal bastard) the floor hard and unforgiving under his knees (come on, Sherlock, come on) coat in a puddle by his feet (I don't have friends I just have one) scarf strewn just past it (you are brilliant, you are fantastic) books, papers, toast, violin on floor (one more miracle, Sherlock, don't be dead) white powder (one, two, one, two, breathe, breathe, goddamnit breathe!) white powder (stop being so still) spoon from this morning's tea (heel of hand over sternum, CPR training, first year med school) Sherlock's Bunsen burner (don't you dare) syringe (stop it, Sherlock, just stop it) John's syringe (why won't you wake up?) taken from John's medical kit (you completely selfish arse) should never have left it there (three years was bad enough, oh god) white powder (lips over yours but it isn't kissing) white powder (you need to live so I can kiss you again) white powder (can't lose you again) white powder (please).

Please tell me you're all right.

It's Baskerville all over again, heart pounding like a rabbit's, head dizzy, room spinning. It doesn't make sense. None of this makes sense.

Jesus, no.

Sherlock.

Floor.

Pale.

Not moving.

Not breathing.

No.

The police sirens are suddenly coming from outside their flat and the last thing John can remember thinking is that, well, it's a good thing Lestrade knows Sherlock and John so well. Then his world dissolves into yelling and beeping and running and the ruthless closing swing of hospital double doors as doctors cart Sherlock off to where John can't follow.

Please tell me you're all right.

Please.

xxxxxxxxxx

Over the duration of their friendship, John Watson has told Sherlock Holmes many things. He's told him bits about Afghanistan – the odd patches of green, the fantastic view of the stars; the red couch that had been in his commanding officer's quarters, the sole piece of decent furniture in the entire barracks. He's told him about his family, growing up bickering with Harry in the countryside before they moved here so John could go to med school. He's told Sherlock about his harrowing internship, his first girlfriend, his love for Dr. Who. He tells Sherlock little snippets of his day every time he comes home.

But John will never, ever tell Sherlock about the thirty-four hours he had to sit by his friend's hospital bed, reddened eyes never leaving the line of the heart monitor, not once. He will never speak of them, never mention the thoughts that had run through his head or the spastic clench and unclench of his own heart. He will never say how it felt like a lightning strike to his very soul, thinking that his flatmate and best friend and his heart – yes, heart, because if John is Sherlock's then Sherlock can only ever be John's – was dead again. Again.

The utter stillness beneath his fingertips. Lips touching lips and feeling no breath. And afterward, in the hard plastic hospital chair, wondering how different things would have been if he'd just said something, anything, that fateful day with the violin bow. If things would have changed. If they wouldn't have come to this.

It's all right, though, that John will never tell Sherlock, because Sherlock will never ask. Not for lack of curiosity, though, but Sherlock will know by then. He will know that there are some things about John Watson he will never learn: how it felt to be bleeding out onto the desert sand, what the split-second of nothingness was like as the bullet tore through his shoulder, why he decided to become a doctor in the first place, and now, what those thirty-four hours were like. He will know this, and he will accept it, and John will read in every hard-edged kiss, every frantic and reverent touch thereafter, just what that knowledge does to Sherlock every day.

xxxxxxxxxx

Lestrade is there at the beginning, sitting with John in the waiting room as Sherlock is off in the private rooms having his stomach pumped or whatever the standard procedure is for heroin overdoses. They shift on the uncomfortable chairs and stare in silence at the beige walls. Lestrade's phone beeps no less than seven times but he ignores them all until John tells him very, very quietly, I'll be all right.

This time Lestrade leaves with a gentle squeeze of his shoulder and John offers a brittle smile. "Tell me when he wakes up, yeah?" Lestrade says, and strides out of the emergency room waiting area. John appreciates the spoken when more than the unspoken if, because it'll help him keep afloat a little longer.

The hospital room is private, and large, and probably very expensive, and has Mycroft Holmes written all over it. John is grateful in a bitter way, but thankfully when Mycroft visits (fifteen hours into the wait) he does nothing more than check all the charts, nod at John, and stand for one tight-lipped moment at the foot of his little brother's bed. There is something about his expression that tells John he's seen this before and he feels a brief and disconcerting flash of sympathy for the older Holmes. Then Mycroft's diplomatic impassivity is back in place and he's sweeping out the door to plan the next war or corporate takedown or whatever it is he really does with his time. The idle thought of Mycroft on a horse in the old British army uniform crosses John's mind and he spends a good six minutes giggling hysterically before the lack of an answering chuckle sobers him up.

Molly is the one who brings him food, a little carton of stir-fried beef on rice that tastes as bland as hospital food can ever be. She chokes up a little as she places it on the little table beside John and flees before she can break down completely. It seems an odd thing to be thankful for, her disappearance, but thankful John is. He doesn't think he can handle a sobbing Molly on top of everything else.

He doesn't realize that he's shifted into efficient doctor mode until Sherlock wakes up completely and efficient doctor disappears. Contrary to popular belief, when someone resurfaces to the conscious world, it is not in some dramatic opening of eyes, followed by the heartfelt murmur of a name. Awareness returns in stages, with sight being the last to return. Therefore John is already on alert, standing in the far corner by the window, when Sherlock finally twitches a little in bed and cracks his eyes open to the dim light of the closed curtains.

Efficient Doctor Watson disappears in a whoosh of breath, and leaves plain old John Watson to deal with this aftermath.

They spend another hour just looking at each other as Sherlock mentally shakes himself loose from his drug-addled haze and John fights to keep the lid on everything that bubbled to the surface at the sight of those verdigris eyes (half-open and staring at nothing, having none of the life in them that he's loved since day one). John watches Sherlock come to terms with his surroundings, with his situation, with the fact that he is very much alive, and with the fact that John is right there, torn between throttling the mad bastard with his IV tube and latching onto him like a limpet and never letting go again. John himself settles for standing there, one fist clenched tight on the white, white window sill (white powder and pumping one, two, one, two, breathe, breathe) and the other hanging limply by his side. He stands there and waits (thirty-five hours and counting of waiting, now, and though it's nothing to three years it's still so much worse because then John didn't know) until Sherlock coughs hoarsely and says, in a scratchy voice, "John?"

John stays very still and waits. Sherlock's gaze skitters around the room as he tries to focus, tries to blink away the medication haze and the consequences of an almost-lethal dose of heroin. "John." He swallows audibly, wincing as he chafes his still-raw throat. "I–"

"Am a completely and outright selfish fucking idiot," John finishes for him, cutting and livid but utterly, utterly relieved. Sherlock shrinks a little, looking appropriately shamefaced, and John's shoulders sag as his head tips back and Christ, does he laugh, hysterical and shocked (shock, one, three, seven seconds of shock in the doorway as he stares at Sherlock's limp form on the living room floor). He falls back against the wall as his shoulders shake, and when it's petered out he discovers Sherlock's looking at him with a peeved expression – almost a childish pout, even.

"Oh no you don't, Sherlock. You've no right to look at me like that, not after what you just did." John points an accusing finger at Sherlock and he blanches. "You – do you have any idea what you did to me? What the bloody hell were you thinking when you went home and you – and you–" His hand trembles as wildly as his voice and he breaks off, relief lost to inner turmoil. His laugh has morphed into a pained, manic sort of smile on his face that feels unbearably brittle and stretched.

"I was only trying to make it stop." That Sherlock is so blatantly candid about this – about anything, really – knocks the floor right out from under John and makes it hard for him to breath. The consulting detective has his head turned to the side, planes of his face drawn taut, teeth bared in a grimace. It is devastation, it is everything Sherlock has not wanted to lose this past year that he has anyway, and the one thing he has wanted to lose that John has made him keep. But John has lost things, himself, and he has held both these alternatives in his hands, and he knows which of them the only one they both can take is.

"No. You listen to me now, Sherlock Holmes." The smile drops off John's face as he turns serious, and for once Sherlock does shut up and listen. John strides over to stand at the foot of Sherlock's bed, plants one hand on the railing. "You don't get to do this to yourself, do you hear me? You tried to tell me – you did,that day in the flat, by the couch that I was your heart. Me. So your heart isn't entirely your own, not anymore, so you can't just go and make executive decisions on it without checking with me first. I – I can't even begin to imagine how difficult this will be for you – I don't think there's a word in the English language that covers it – but I'll be damned if I won't be right there with you every goddamn degenerative step of the way. And if it comes to it, I will start heading to the gym first thing every day and lift weights so I can carry all six feet of your maddening, stupid, brilliant person to crime scenes. Is that clear?"

In the hospital bed Sherlock has his arms around himself, fingers digging into his ribs through the cloth of his shirt as the sheer force of them is all that is holding his body together. He's gone so pale that under the harsh hospital lighting he looks nearly translucent. John grips the railing so hard his knuckles go white and takes in a shaky breath.

"I already had to bury you once." Damnit, he's told himself he won't cry. John grits his teeth and tries to stop his voice from choking. "Please don't make me do it again."

Sherlock simply presses his lips together so tightly they're almost white and turns his head away. It's irritating and a little pitiful. John heaves a put-upon sigh; relief and helplessness make him a little mean. "Well what would you do if I died today?"

"I'd die tomorrow."

The words are stripped and quiet and so very, very honest that they make John's heart jump to his throat as he looks up and meets Sherlock's eyes. The look they give him is heart-stopping in its intensity. For a long moment they simply gaze at each other, Sherlock all defiant honesty and John simultaneously touched and wrecked. Then John pries his hands from the railing and goes round to sit in the chair he's pulled up by Sherlock's bed. He takes Sherlock's hand in both of his, mindful of the needles and tubes, and brings it to his lips. It trembles under his touch. He grips it tighter. Sherlock clutches right back.

"I would really much prefer to not have to go through another time when I did not have you," Sherlock says quietly, and John chokes out a laugh.

"Mad bastard," he manages, for all his throat feels choked with tears, and Sherlock smiles. For that moment, in the muted morning inside a private hospital room at St. Bart's, with Sherlock on the excuse for a bed and John turning Sherlock's fingers white with his grip, their eyes locked on each other's as if it might kill them to look away, things feel all right. Things do not feel like they might come apart.