Warning: Some gore and mild language for this chapter.

A/N: This is my first effort at Sherlock fanfiction, and I hope it's as fun to read as it is to write :) Thanks to fritz42 for the endless encouragement. To anyone concerned about my pieces in other fandoms, fear not, they will be continuing as normal.

B xxx

To Light Another's Path: Chapter One

Flashes of blue light ricocheted down the alley's walls, tingeing rubbish and filth in violet hues. The corpse lay on its back, brown, blank eyes staring at the narrow strip of overcast London sky above. Her pallid lips were lax and slightly parted, revealing the dull ivory gleam of teeth, straight but for one crooked bottom incisor. The victim's clothes were still wrapped around her form, the wings of the navy blue coat caught beneath her shoulders: a dark backdrop to the bloody wound that carved its smile into her neck.

Sherlock pressed a finger to the injury, the thin film of the latex gloves doing nothing to protect his skin from the brumal edge of the winter air. It was deep, no doubt cause of death. He could see a shallow pool of blood caught in the cleft of the slash, coagulated as her body cooled. The skin at the wound's edge was waxy, the cells dead before anything like healing could begin. Not that she could have recovered from the fatal blow, of course.

'Tell me what you see.'

He had no need to turn his head and direct the question; John would know it was meant for him. The staccato click of his knees as he hunkered down at Sherlock's side seemed loud in the narrow alleyway, and those gentle, healing hands slid over the fleshy remains of what had, little more than a day ago, been a living, breathing person.

In the past, Sherlock would not have bothered to acknowledge the corpse's fled humanity – at least not beyond that which the case required. A body was nothing more than a stack of clues to him, and in that regard he had not changed, but he knew John saw things differently: their dichotomous views of empathy and information.

John would still see the woman as a patient, even if she was beyond the reach of his care, and he would treat her as such. Sherlock would lose himself in the fugue of data her remains had to offer, and in their own ways they would both see the person she had been.

'One knife wound to the neck, slicing through her trachea and carotid artery.' John grimaced, his eyes dark with pity as his covered fingertips probed at the wound before moving down to her sternum, and then checking her hands. 'No real defensive wounds; one broken fingernail, but that's it. She would have died within a few minutes.'

Sherlock glanced sideways, watching John carefully. That weathered face was pale from the cold: vaso-constriction carrying his blood away to the warm core of him, keeping his temperature stable while allowing his extremities to suffer. His strong jaw clenched tight, molars crushed together as the unfocussed distress found a futile outlet. It must be blinding, Sherlock thought, because how else could the obvious be so easily over-looked? John was not stupid, but he was still not observing anything of note.

'What else?' he prompted, ignoring the shift of Lestrade's boots on the grimy ground and Anderson's clipped sigh of impatience. They could wait. They had, after all, called for his help.

John gave a small shake of his head, glancing over and meeting Sherlock's eyes with a faintly knowing look. It was a pattern they had fallen into at every crime scene. Sherlock observed, consumed and deduced the knowledge within moments, only taking extra time to cement the details in his mind. He knew his abilities were far beyond what most people considered normal, but John found them fascinating. He took an interest, and Sherlock found himself returning the effort. Perhaps he would never be able to tune John's mind to the level of his own, but he wanted to give John a taste of it: that quivering satisfaction of taking the sum of minutiae available and painting a masterpiece of truth from its fragments.

And so he demanded that John push himself and enhance his shallow field of view. Success was rather limited.

He watched John's gaze sweep the body, and finally, he saw the moment that focus shifted, when John stopped seeing a person –twenty-seven,workaholic,longedtotravelbutneverhadthetime and observed the facts instead.

'Where's all the blood?'

Sherlock smiled, allowing himself the faintest exhalation of something like relief. That it took minutes for John to notice what he had picked out in a heartbeat was perhaps not the most encouraging, but neither Lestrade (distracted by the divorce, functioning below his usual efficiency) or Anderson (merely incompetent) had brought themselves to take in this one salient point.

A weight in the pocket of her coat guided Sherlock's fingers, and he tugged the phone free, peeling one glove off with a snap as he allowed the information on the woman's life to scroll by beneath his touch.

'Sophie Lattimer. She wasn't killed here,' he said at last, getting to his feet and facing Lestrade. The Detective Inspector's hand was pinched over the bridge of his nose, and he managed one curt nod: a simple gesture of encouragement. Not that Sherlock needed it. 'If she were, the alley would be covered in blood, as would her clothes.'

'The killer re-dressed her?' John squinted doubtfully down at the woman. 'They're a good fit, which says this was planned. but the knife wound is clumsy...'

'And with a narrow blade inadequate for the job. The wound is ragged where it was forced. The clothes fit because they are her own: cheap, high street brand pulled out of her wardrobe in a hurry, but –' Sherlock narrowed his eyes, taking in the whole picture. 'She did not dress herself.'

'What makes you say that?' Lestrade dropped his hand, his gaze raking blindly over the body at their feet.

Sherlock let out a harsh everyone-is-an-idiot sigh, feeling John twitch at his side before inching just fractionally closer. It was not a reprimand or a warning, but a hint of movement that was the faintest presence of a leash on Sherlock's impatience. There was a mute understanding of the fact that with brilliance came arrogance, and a silent request from John to spare the Yard from its bite.

'Any woman willing to spend almost a month's wages on a pair of Manolo Blahnik shoes,' he gestured to the elegant stilettos, so out of place they seemed obscene amidst the gutter's filth, 'would not match them with an off-the rack skirt, polyester blouse and frankly poor quality coat. No doubt she saved her best clothes for work; financial director, judging from the array of stock market apps on her phone, and wore the others at home in her rare hours outside the office.'

He paused, gathering the details around himself, all too aware of the lost-at-sea looks he was receiving from everyone within earshot. 'She was nude when she was killed, as evidenced by the dry blood.' He crouched down, flicking up the bottom of her blouse to reveal a sepia patina across her skin. 'The killer wiped it off her hands and chest so it wouldn't show around the edges of the clothes, but forgot her feet. She wasn't wearing shoes or hosiery, and droplets got caught between her toes, suggesting she was standing at the time of the attack. The blow was dealt from behind from someone she trusted. A lover.'

'Because she had no clothes on?' John asked, and Sherlock gave a brief nod, his lips tilting in a flicker of a smile as he looked up at John from where he was crouched once more at the woman's side.

'To whom else would you expose your bare back? Whoever it was, she did not expect any kind of attack. Judging from the high quality threads caught on the heel of the shoe, wool blend, double twist pile, she was murdered in a high-end apartment. Her home. That's where you'll find the blood and,' he glanced at his watch, seeing the hands hovering over three in the afternoon, 'probably the identity of the murderous lover, if you hurry.'

He moved to stand up, shifting his weight with no direct thought from his mind, yet something – some indefinable sense of wrongmade his muscles twitch and weaken. In front of him, the corpse blurred, her sharp outline turning cloudy as his head spun. It passed in a matter of seconds, leaving him blinking in confusion with the warm weight of someone's hand on his elbow.

'All right?' John's question was sharp; battle-edged, and Sherlock shivered beneath the burden of that probing gaze. 'When was the last time you ate?'

Sherlock's only answer was a faint snort, and he eased himself free of John's grasp as he straightened his coat and peeled the clinging latex free from his left hand. 'I'm fine,' he replied curtly, stepping back from the body and freeing himself from the foetid grasp of the narrow alley's airspace. 'The address is in the phone.' He passed it to Lestrade.

Lestrade nodded, his gaze falling pityingly on the woman once more before he gestured to Anderson and his team. 'Start processing. We'll investigate the apartment and see what we can find.' He held up a hand, his expression grim as Sherlock almost walked into the warm spread of his palm. 'I'll text if we need you again.'

'A waste of time,' Sherlock snapped, scowling as another shudder worked its way down his spine. The day was dying, dragged away by winter's dark grasp, and the cold, damp air seemed to seep around the edges of his coat and make nests next to his skin. 'John and I will meet you there.'

He dodged around the bulk of Lestrade before he could protest, heading towards the main road. He knew without looking that John would follow, no doubt with an apologetic glance and smile. He seemed to have made it his mission in life to smooth the ruffled feathers Sherlock left wherever he went. He honestly did not know why John bothered. The opinions of others had no bearing; it made no difference to the Work, after all...

Another shudder ripped through his body, rousing a groaning cacophony of aches in its wake. His knees felt like crumbling concrete, and the muscles in his thighs shook from the effort of each step. Perhaps John was right after all. The last meal had been a long time ago. As soon as the case allowed, he would eat something: a token gesture to the body that carried around the gleam of his mind.

He took a deep breath through his nose, taking a moment to appreciate the smell of London – carexhaust,dieselandunleaded,theeverpresentthreatofrain,decayandthefaintliquidfragranceoftheThames – before raising his hand to flag down a passing taxi. The hackney cab slowed at the kerb, a sable, familiar bulk, and Sherlock suppressed a sigh of relief as he eased himself into the uncomfortable cradle of the seat.

'Admiral Walk,' he instructed the driver, watching the scatter of beads and other miscellany swing from the rear-view mirror as the vehicle pulled out into traffic. It was vaguely hypnotic, an unintentional metronome to the elegant roll of the cab, and Sherlock found himself staring blankly through the scuffed veil of the partition.

'You're not all right.'

He shut his eyes, trying to ignore the fact that they burned along the seam of his eyelids as he dragged them open again. Of course, John would choose now to be observant. Perhaps he was naturally more attentive to the details of the living, rather than the dead. He was a doctor, after all, a detective of the biological malaise of the populace, and one who seemed aggravatingly attuned to the soft ebb and flux of both Sherlock's mood and his health.

'What makes you say that?' he asked, genuinely curious. He had not been ill in the year John had known him, at least, nothing that was not self-inflicted. Injured, yes, and mildly poisoned by one experiment taking a turn for the unexpected, but nothing more serious. John had not even been called upon to use the hospital grade overdose kit Sherlock knew he had gathered together after Lestrade's so-called drugs bust. There had simply been no need. Even during his deepest fits of ennui, Sherlock had not turned back to his recreational substance of choice. Yet here John was, no doubt seeing far more in the lingering betrayal of Sherlock's body than he himself was willing to give away.

'You're always pale, Sherlock,' John pointed out, 'but now you're almost grey. More obvious is the way you're moving – stiff and sore – like you're the one with the dodgy leg.' A faint smile curved over John's mouth, derisive at the mention of his psychosomatic limp, now long gone unless he was emotionally exhausted.

Sherlock tried to return it, but his face felt stiff and unnatural, his muscles unresponsive, so he aborted the attempt before giving it a chance. He closed his eyes again, aggravated by the low, crunching ache that had started to throb at his temples. Probably caused by the sick, sallow fluorescence of the taxi's interior light, he thought.

The cool brush of John's fingers on his brow made him recoil, almost banging his head on the window as instinct jerked sore muscles into action. John's hand wavered, still raised, and Sherlock saw the moment the decision was made to push forward, rather than retreat. John's thin lips tightened further, his shoulders tensing slightly as he repeated the gesture, knowing full well there was nowhere for Sherlock to go. He was effectively pinned in the corner, unable to avoid the gentle examination.

It was the simplest of touches, banal in its innocence, but Sherlock still found himself staring, his gaze darting around John's face in a hungry quest for clues. Emotions had never been his area, but months of familiarity had made John's expressions less opaque than most, and he was far too familiar with the concern he could read from the lines around John's eyes.

'Maybe I dragged something back from the surgery,' he mused quietly, shifting closer along the seat and pressing his palm across Sherlock's brow. 'There's plenty going around. 'Flu season and all that.'

'No.' The word cracked in the air between them, and John raised a doubtful eyebrow. 'I'm not ill, John. I don't have time for it.'

'Let me guess, not while you're on a case. Like eating and sleeping.' John sighed, moving his hand back to the safer, less intimate periphery of Sherlock's wrist. He did not ask permission. He probably thought it was unnecessary in the pursuit of a diagnosis, yet Sherlock realised faintly he could never deny him anyway. 'Getting sick isn't something you can control, you know.'

'Mind over matter; there have been several studies...' Sherlock's voice faded as John looked up at him from beneath a frown, the lines bracketing his lips deepening in doubt. Clearly this was not the time for further enlightenment.

'I can't tell if you have a fever or not, not when you've been standing out in the cold for more than an hour, but we should go back to Baker Street.'

'No!' Sherlock gripped John's wrist, deposing his hand from where cool, dry fingers pressed against his radial pulse. 'I am in adequate health to examine the flat. It could mean the difference between a murderer in a cell or walking the streets.'

It was a good argument, one he wielded before him like a cattle prod at times. It rarely failed to result in eventual surrender. Few normal people could allow the balance of their moral code to come out in favour of bed rest over the capture of a dangerous criminal, but it seemed perhaps this time John had found his tipping point.

'Lestrade is no idiot, Sherlock, whatever you might think. He's more than capable of searching the flat himself. He'll text us if he finds anything interesting. Besides, you said yourself before we even left Baker Street that the case was dull.'

'It is.' He sighed, wishing there was a more intriguing pantheon of iniquity available to him. Many of London's criminals seemed painfully lacking in creativity since Moriarty had gone to ground. 'No locked room, no serial killer... no unique nuance to capture my interest. An open book of a case. Lestrade only asked for me because his workload has reached an intolerable peak. He needs cases solved quickly and without finesse.' He smiled. 'Matches the murder, really.'

'So why are you so keen to see her apartment?' John challenged, sitting back and folding his arms, his chin raised in pugnacious challenge. 'Want to make sure you're right?'

'I know I'm right,' he replied, curving his shoulders and trying not to quiver. The heating of the cab was doing a perfectly adequate job of turning the air to hot velvet around them, but it would only make the steel trap of winter snap all the tighter around them when they reached their destination. 'I live in the eternal hope that perhaps there is something more interesting to be found than a dead body in an alleyway; something that will lift this crime from the mundane and allow it to ascend to the realm of the intriguing.'

He heard the bitten back sound of John's sigh. Not the one he made when he was trying not to smile, but the other one: annoyance. The timbre was lower, and there was a minuscule downwards intonation. Sherlock had heard that sound frequently over the past month since confronting Moriarty at the pool. John was growing increasingly frustrated with the dark moods of boredom and the reckless behaviour they often inspired. He was becoming weary of the way Sherlock's mind turned inwards, destructive and biting, when there was nothing else to occupy the lightning storm of intellect and deduction.

That was the real reason Sherlock wanted to see the apartment, not because the case held any real interest, but simply because he was bored. Returning to Baker Street would be the same as sinking back into those oppressive shadows – allowing the focus of his mind to scatter, sharp and painful to all the unsuspecting targets of his frustration: Mrs Hudson, John, supposedly innocent strangers and, of course, himself.

No, a case – any casewas better than that. His mind needed feeding, exercising, challenging, or it began to walk the twilight avenues of "a bit not good". If he could not deduce the flow of blood and the mystery of particulates then he found himself trapped in a loop of meaningless knowledge flowing ever inwards – the pattern of traffic lights, the life of the postman, the intimate secrets of all those around him – all taking up space on the hard drive of his mind and weighing him down in the sea of irrelevance.

Better to trawl through the mundane that the Yard could offer than subject himself to that again. Before John, he would not have bothered – would have weathered the storm as best he could by whatever means necessary and keep his high standards of intrigue – but now he found himself strangely unwilling to let John witness the true depths to which he could sink. After all, there was every chance that it would be enough to finally break John's strength and drive him away.

No, that would be intolerable.

The taxi pulled up to the kerb, interrupting his thoughts, and he bullied his limbs into activity. John was left to pay the driver as Sherlock eased himself free of the seat and trotted up the steps to the pristine apartment building. It was expensive, but not good enough to keep a doorman on staff. Clearly Ms Lattimer had the satisfaction of a well-paid job in the city and the benefit of some intelligent investments to afford the place, though he would still estimate it beyond the range of her earnings. She had another source of cash, though the relevance of that was open to debate.

A fob system protected the door, and he sighed in irritation before looking at the speaker system to the right. One flat was blissfully nameless, and he smirked as he pressed the button above, waiting for a voice to crackle over the intercom.


Male smoker in their forties, private school education, probably high up on the board of directors in one of the nameless corporations littering London's streets. 'Oh, brilliant!' Sherlock said, allowing a smile and a touch of breathlessness to enter his voice. 'I'm just coming to view the empty flat on the third floor, but the bloody estate agent's late. Could you let me in so I can at least get a look at the building while I wait?'

Next to him, John rolled his eyes, an expression that did nothing to hide the wince. He clearly hated it when Sherlock pretended to be normal, slipping with painful ease into a guise like this. Sadly, such things were often more simple than telling the truth. It should not work, the lies and deception, people should ask more questions, throw forth more challenges, but somehow they never did. Strangers were far too content to take what they sensed as truth and damn the consequences. They wanted to see the good in people. As if humanity's default setting was not naturally a grubby sort of malice, but something more worthwhile.

'Of course,' the rough voice replied. 'I hope you like it. The damn place has been empty for months.' A moment later the LED on the door turned green, allowing Sherlock to sweep into the hallway beyond with John at his heels.

'No downstairs neighbour,' Sherlock muttered as he made his way to the lift.

'No one to hear any bumps in the night,' John concluded. 'Maybe the people to either side of her will have heard something?'

Sherlock was already shaking his head, taking in the serial number of the lift with a quick flick of the eyes. 'Premium Central London apartments built for the delight of the drones in the financial district in 2007 at the peak of the housing market. The apartments are large and spacious, to better validate the extortionate price tag. She had one neighbour across the hall who hasn't been home for more than a week.'


'Post boxes in the lobby. Ms Lattimer occupies suite number eight. The box of number seven has not been emptied for a while.'

John gave a weak huff of laughter, and Sherlock smirked, hearing the unspoken "Amazing!". John said it out loud less these days, perhaps because he was afraid Sherlock would scold him for the needless repetition, but the sentiment was still detectable. John's shoulders, tense since climbing out of the cab, had relaxed, and his murky blue eyes softened as he said, 'If you are coming down with something, it's not slowing you down much.'

'As I said, mind over matter.'

The smug expression on John's face was entirely too sharp – too knowing – for Sherlock's liking, and he raised a questioning eyebrow as John leaned back. 'So you admit something's wrong?'

'I've done nothing of the sort,' Sherlock replied with a sniff as the flat chime of the doors announced their arrival on the relevant floor. He swept through, eager to escape the unsettling focus of John's gaze as he stepped onto the floor of a well lit hallway. Broad windows gave a view of London's bustle beyond, not high enough to afford a skyline vista, but rather the more claustrophobic panorama of the street below.

The door to number seven was shut firm to their right, and the intervening space of white marble floor was unsullied by tell-tale footprints. Yet it was the scent that caught Sherlock's attention: astringent and treble. 'Bleach. Someone's been cleaning.'

'The door's not shut,' John murmured, jerking his head towards number eight, and Sherlock followed his motion. Sure enough, the latch had sprung too soon, preventing the locking mechanism from sliding home into its socket. Just as well, because his picks would be no good against the swipe card system in place.

Quietly, he inched closer, slipping his hands into leather gloves as he carefully avoided the handle; it would do him no favours with the Met if he smudged any available fingerprints. Prying the door open a fraction of an inch, he peered inside, taking in the gloom that had fallen at sunset. There were no obvious signs of movement, nor sounds from within. Whoever had been here before, no more than a few hours ago judging by the scent of the bleach, had clearly already made their departure.

The soft whirr of the lift made Sherlock pause, lifting his eyebrow in surprise as John pressed himself against the wall beside it. His hand was on the brutish shape of the Browning in his pocket. It was rare the gun was left at Baker Street these days, the risk of being caught with it was outweighed by the likelihood of needing to shoot someone. It was comforting to see John like this, his character twisting to reveal a different facet of his personality: not just flatmate, doctor, friend – but soldier and protector.

Only when the lift doors parted to reveal Lestrade and Donovan did they both relax, John's hand falling back to his side as his features radiated unassuming innocence.

'What's the freak doing here?' Donovan demanded, unoriginal as always.

Sherlock noticed the faint clench of Lestrade's jaw. The sergeant's taunts often went by with barely a reprimand. This time was fractionally different. 'He found out where the victim lived, something neither you or Anderson could deliver.' He turned back to Sherlock with a frown. 'If you've been in there already...'

'The scene is undisturbed, and the door was unlocked when we got here. No doubt left unlatched by whoever found it necessary to wipe bleach all across the floor.' Sherlock waved a hand around. 'Someone has been attempting to cover their tracks.'

'Been watching too many episodes of CSI,' Lestrade muttered, giving a sniff before approaching the doorway, ignoring Sherlock's baffled expression.

'TV,' John supplied, smiling at Sherlock's grimace of disbelief. 'Turns out it's not all useless after all.'

'Dull.' Sherlock watched as Lestrade and Donovan entered the suite, walking carefully along the edges of the room rather than striding across the middle. Clearly they were making an effort to spare the evidence for Anderson's inept efforts, although Sherlock could have told them they were wasting their time. The pile of the carpet was groomed, newly vacuumed, and the stench of bleach only intensified as they left the petite hallway and moved into the open plan rooms beyond.

Sherlock narrowed his eyes, frowning at the disparity. The body was dumped in an alleyway, neither particularly well-hidden or cleaned, though some clumsy efforts had been made. Yet the apartment was immaculate. The few items of sentimental value were carefully arranged, yet there was no dust around them – making it impossible to tell if they had been disturbed. The carpet was flawless – no track marks, not even any coffee or wine stains, and the bedroom was eerily similar.

There should have been blood everywhere. A severed carotid would result in arterial spray, yet the bed was made in white linen, completely clean, and the walls were unblemished. If it were not for the chemical fragrance of bleach, Sherlock could almost believe he had been mistaken. No, someone had detailed this apartment, meticulously wiping away the evidence.

'Interesting,' he murmured, a frisson of curiosity rippling through his mind. 'There was an accomplice. Either they were responsible for disposing of the body, or for cleaning the room.' He splayed his fingers out, jabbing them down towards the floor in emphasis. 'Whoever cleared up this apartment was attentive to detail and thorough – dispassionate. The one who dealt with the body was clumsy and frightened.'

'You sure she was killed here?' Lestrade demanded, his eyebrows raised. 'If you're wrong, you could save us a lot of time and just admit it.'

Sherlock smirked, and mutely pointed one finger at the ceiling above their heads. It was not much, easily missed, but a few dark spots lingered on the white paint near the light fitting. 'The peak of the arterial spray on the first cut,' he murmured. 'I'm not wrong. This is your murder scene. Get Anderson to check the bedstead, if he's capable. The black paint might hide more stains. Clearly her bedding has been disposed of, but there will be empty hangars in the wardrobe, and –'

His voice died in his throat, quelled by a bright, sudden stab of pain through his head. He could feel the pili on his arms coaxed upright by another shiver, and this time there was no relief. It did not pass like a wave, but instead lingered, making muscles jump and twitch. The longing to rest was abrupt and keening – loathsome as it speared through his concentration and scattered his deductions to the wind, leaving him groping helplessly for what he had been about to say.

'And –?' Donovan prompted, her lips quivering around a sneer.

'Find the lover and you will find your answers. Unless that simple task is beyond you?' Sherlock bit out, trying to hide the abrupt derailment of his train of thought. Perhaps John was right after all: Baker Street was calling.

He swept back out into the main room with as much dignity as he could muster, trying not to obviously slump against the wall as he spotted John carefully perusing the scant few photographs decorating the place. The room was like a hollow shell: a house rather than a home, but although that thought niggled at the edge of his mind Sherlock could not make anything of it.

Hateful. Hateful! How could this happen? How could his mind be brought low with such ease: a victim to the whims of his insignificant flesh? It made him want to claw at himself and tear aside the choking shroud of weakness that had collected him so swiftly in its grasp, but he found he barely had strength to lift his arms. When he called John's name it only got worse, as if the simple exercise of pushing air past his vocal chords was a Herculean task.


He lifted his head at the weak summons, the distant fog of thought in his eyes fading into an intent look of sympathy that Sherlock found both wretched and gratifying. Clearly he now looked as bad as he felt, and John's attention was absolute. He took it all in with a practised eye, moving with prompt efficiency to Sherlock's side before shaking his head.

'You daft bugger.' Fondness seeped into his voice, warm and comforting, as if Sherlock had done something stupid but not at all unexpected. 'Come on, let's get you home.'

And, for once, Sherlock was happy to surrender himself to another's assistance, weak and trusting as John led him away.