"Come on, John, we're losing him!"

John vaults full-speed over the felled owl cage that the criminal had thrown to the snowy street right after Sherlock. The grimy man gives a shout, throws a spell over his shoulder, and John counters with a backhanded shield charm (the spell bounces off, hits the hanging sign for Ollivander's, and it explodes spectacularly on contact). John shouts at the top of his lungs for everyone to get out of the way, and there are screams and a great jostling of bodies just as the man ducks sideways into Knockturn Alley.

Sherlock follows, and John follows him.

Spells fly, lighting the dark alley with color (one of Sherlock's stunning spells rebounds and knocks a raven from a sign post). John grabs Sherlock by the back of his long coat and tosses the both of them into a darker side-alley when another Blasting Curse sails their way (showering them with chips of brick and mortar when it hits above their heads).

John rebounds first, and with a cry of "DEPULSO!" their assailant goes flying through the close air and strikes the wall of the nearest pawn shop. Knockturn Alley's finest have all suddenly and wisely cleared out of the streets, into the dodgy shops and crevices, and so there's no one to help the criminal when he hits the snowy ground with a crack.

The cornered man attempts to shakily lift himself from the ground or crawl away, but John is out in the open now, wand on him.

"Incarcerous," Sherlock says breathlessly when he approaches behind John, and ropes spring from the end of his wand to bind the grounded man's hands.

John tilts his head back, fighting for breath amidst the uncontrollable giggling that's suddenly seized him. Sherlock joins in hopelessly, leaning back against the nearest wall for support. John takes a seat on the incarcerated man's back and hangs his head between his knees as breath and laughter fight for dominance.

"You didn't even tell me what this bloke's done," John says, shaking his head. "Or his bloody name, even." That doesn't stop John from following him. It never has.

"Joe Harrison," Sherlock says between attempting to breathe. "Took a little something from our old friend Andrew West."

"West? Hell, that was years ago, Sherlock," John adds (and memories of running through Chelsea away from the sound of Weasley's Whiz-Bangs and giggling like fools in the tube station years ago cause another flood of laughter to take him). "He's Ministry now, right?"

"Right," Sherlock says, straightening his collar needlessly after their run. "Deals in foreign relations. This fellow got his hands on some rather sensitive information that we'd rather not leave the country, hence—" He waves his hand at Harrison and John on the ground. "Aurors should be after us presently." His posture speaks of impatience, but there's a crooked smile on his face that he saves for John and the Chase.

John looks up with a wide smile, chest heaving. "I've got it figured out. Today's your birthday."

And then Sherlock looks completely scandalized, shocked into wordless horror. In all the years they'd been together, Sherlock had never even let on that he had a birthday (as if he'd suddenly decided to crawl out of the ether twenty-seven years ago and coalesce into a human being).

"How could you possibly—" And then Sherlock's face frosts over in anger. "Mycroft."

John laughs loudly, breath fogging with every gasp.

Not a minute later, there are two cracks from somewhere near them, and the heads that had begun to peer out from the alleys and doorways disappear back into hiding. The two Aurors stride quickly over, and John's smile goes full-blown.

"Watson," Lestrade says with a gruff laugh. "Thought I'd find you two behind this."

"Business as usual." John stands, grabs both of Lestrade's hands in his for a warm shake.

"Still vigilante, then?" Lestrade shoves his hands deep into his pockets for warmth. "Ministry could use you two, y'know. You'd make a damn good Auror, Watson."

Sherlock's eyes narrow on the woman behind Lestrade, who meets the look with a frown. Sally Donovan leans down and picks the stunned Joe Harrison off the ground and grunts under the weight. "You two 've got no right to go around causing all this panic, you know," she cuts into the conversation. "Leave Auror work to Aurors."

"When the Aurors learn to do their job properly, I'll no longer need to do it for them," Sherlock says icily.

Sally hisses and frowns this time at John. "Once a Slytherin, always a Slytherin," she murmurs. "I read your book," she raises her voice at Sherlock boastfully. "Ridiculous. The Magic of Deduction?"

"You didn't read my book," Sherlock mutters dully.

"Looks like rubbish anyway," she shoots back.

"Science and magic have more in common that you'd like to acknowledge, and if you perhaps practiced a bit of mental exercise, I wouldn't have to catch your traitors for you." He continues through her affronted expression. "If used in conjunction properly, magic and science can make strange but remarkable bedfellows."

"Yeah, well, the two of you would know all about that, wouldn't you?" It's meant to be a jab. John just laughs, especially when Sherlock's ears still go pink.

"If you ever decide to go off independent work," Lestrade says warmly once Donovan Apparates with Harrison in tow, "I'll put in a word for you with Potter."

"I like it here, thanks," John says, clapping Lestrade on the arm. "You should come by sometime, have a chat."

Sherlock frowns lightly, which only makes the grin on John's face expand exponentially.

"221b Baker Street," John adds, and then he turns and takes Sherlock's hand in his own, pulling him away to the sound of Lestrade Apparating off again.

Their landlady is a wonderful old woman named Mrs. Hudson, remarkably patient and unbelievably understanding. When Sherlock attempts to heat the tea with his wand at four in the morning and nearly blows a hole in the building, John's mostly concerned that she'll discover the fact that they're not the unassuming couple she thought them to be and are actually an unassuming couple of wizards. Instead, she gives them a broad wink and bustles off downstairs to call her great nephew to patch it all up. Later, she tells them that she's the only Squib in a family of wizards (over tea and biscuits in her sitting room), and as long as they don't try to blow up the flat again, she really doesn't mind.

When they bustle into the warm foyer from the icy January wind after the Joe Harrison incident, the post is waiting for them on the table by the stairs (Sherlock still doesn't understand Muggle post, but the occasional owl at the window doesn't attract as much attention as John had thought). John sifts through it (reading around Sherlock, who is trying to get John's jacket off while he reads) and he gives a little noise of recognition at the last.

"My mum," John says lightly, turning the envelope over in examination.

Sherlock peers over John's shoulder, kisses at his ear while he's close, and John swats him away with a smirk. "What does she want?"

"Says Mycroft sent her an owl about your birthday."

Sherlock gives a low growl, and John chuckles in reply, reaching around to scrub his fingertips fondly through the curls at the back of Sherlock's head.

"She's got you opera tickets," John says with growing awe as he pulls the gift from the envelope. "Bloody hell, me too."

Sherlock frowns.

"Oh, come on," John chides. "My mum got us opera tickets for your birthday! My mum, who hasn't even got herself a new house dress in years. You're writing her a thank you—No, we're going to see her this weekend and you're saying thanks in person."

Sherlock grumbles.

"Why don't you want anyone knowing when your birthday is?" John asks.

"Because it doesn't matter," Sherlock utters grayly. "What does my being pushed from my mother's loins on a Saturday have to do with anything? Exactly," he replies before John can get a word in. He's up the stairs to the flat in twos.

"Yeah, well," John calls up, following him, "you could say the same thing about Christmas, and you don't have a problem with Christmas."

They meet in the kitchen, and somehow the smaller man has the taller pinned up against the counter, eyes locking.

"So you're getting a birthday present, and you're not going to complain about it," John says very plainly (and very close).

"Hnn," Sherlock replies eloquently when John hits his knees.

"He just wants a look," John pleads, running after Sarah when she moves away.

"They're people, not experiments," Sarah reminds him, but her tone is even, and she hasn't stopped smiling since he walked in the door to her ward.

"He wants to help," John goes on, but then he realizes this probably isn't completely true. "Well, he wants to learn, and that's sort of helping. A bit. I mean, the more he knows, the better he can solve cases, right?"

"He's not even an Auror," Sarah reminds him.

"Yeah, well, the Aurors come to him for help, don't they? Just give us five minutes with them."

She stops, and even though she's very glad to see him, there's pinched concern between her brows. "What is five minutes in the Janus Thickey Ward going to do for anyone?"

John doesn't back down, but he's calm. "He's studying Memory Charms. The more he knows about the long-term damage—"

"I can't, John," she replies softly. "He can't poke and prod people like they're not human. Not today." She sighs heavily, then a sad smile returns to her face. "I'm really glad you came to see me. Both of you. Look, if you come back next week, I might be able to arrange... I don't know, an interview with someone. But no experiments."

"No experiments," John echoes, grinning. He leaves a kiss at Sarah's cheek. "You're brilliant, thank you. Lovely to see you again."

He's off and running back down the hall, back to Sherlock, who kisses John all over his face and hair and ears in thanks.

There's a loud thump and a boom from downstairs, and John jolts awake (visions of exploding Quidditch hoops fading from behind his eyelids). He hops into his pants before he rushes downstairs, disheveled and half-asleep, but with his wand raised and ready for a fight.

And he dissolves into gales of laughter at the look on Sherlock's face, the circle burned into Mrs. Hudson's carpet, and the litter of dead bees all over the sitting room.

AN: AND THAT'S THE END! Hope no one was expecting anything wonderful from the epilogue, it's just a neat little coda. I wanna tell everyone HOW AMAZING YOU ALL ARE FOR BEING SO AWESOME TO ME FOR THE DURATION OF THIS FIC, and I love every single one of you reading this. I need to you to know that! I really loved writing all of this, and y'all made it that much more fun for me. I don't know if I'll be coming back to this verse or not, time will tell (for those who don't know, I am currently researching another BBCSherlock AU, and I'll give you this clue: jazz). Thanks again, so so much; leave us some love and def. don't forget to STAY AWESOME!