AN: To those waiting on the next instalment of Carbon Copy and Give You the Sun, they are coming. I'm sorry for the silence – Real Life has kind of been beating the crap out of me. But, while I go and continue working on those other two, here – have a Post-Reichenbach Sherlock fic; my first addition to this amazing fandom.

Disclaimer: I don't own Sherlock. Also, not a forensic scientist, so that which I know about entry and exit wounds I learnt from the combined educative forces of NCIS and Google.

Warning: Swear words. Also, spoilers for The Reichenbach Fall, but really – I'd be very surprised if there was anyone in this fandom who still hasn't seen it.

Edit: I've traded in the slightly American swearing that I fell into for some more-suitable British swearing. That's what happens when you read too many fics for American shows with characters who swear as easy as breathing - it influences your own manner of speech, and it's not a good influence. That, and tumblr. Tumblr is a bad influence on the English language.

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Dying from the Exit Wounds

…

A bullet makes a smaller hole going in than it does going out.

Upon impact with the target, the tip of the bullet will fragment and curl back on itself, widening further with every millimetre it travels, and by the time it tears out the other side, depending what sort of bullet it was, it can leave a wound three-to-six times larger than that of the entry point.

John knows this. He should damn well hope he knows it, at least – he's a military doctor, and he's been shot himself. The basic forensics of entry-versus-exit wounds is not an unknown field to him.

But… well. He didn't see this coming, but he maybe should have.

Because Sherlock – on that damnable, damnable day he glanced up from his microscope with a bored expression and told John's life story at a single glance – entered John's life with a bang and left an entry wound in his wake, so small that the doctor didn't even notice it at the time.

He really shouldn't be so surprised. Where there are bangs there's gunfire, and where there's gunfire there's bullet wounds, and "with a bang" is possibly the best way to describe Sherlock's entry into John's life. But at the time – and in all the wonderful, amazing, fantastic, incredible months that soon passed – John never guessed that when Sherlock entered his life it came with a price. Came with a tiny hole – a miniscule entry wound – so small that no one ever even knew it was there.

How could he have guessed, when Sherlock fitted in with him so perfectly it was like he was always meant to be there? Like they're two strangely shaped puzzle pieces that make no sense on their own, but that when joined together somehow make a whole that not only works, but works brilliantly and flawlessly and beautifully.

It's like – and John's aware that this sounds slightly melodramatic, but that doesn't make it any less true – it's like he's lived his whole life without lungs, and then when Sherlock stood up from his microscope and swaggered over to continue his cocky, arrogantly presented description of everything he'd deduced from John at a glance, he'd shoved a set of lungs into the doctor's chest cavity and suddenly – for the first time in his life – John had known what it was like to breathe.

Frankly, John can hardly believe he lived so long without Sherlock in his life, and he can't believe that the time he has known Sherlock has been – by comparison – so short. It's like Sherlock was always supposed to be an integral part of John, and the doctor's life didn't properly start until the World's Only Consulting Detective started splitting the Bakers Street rent with him.

Everything from before – before Sherlock, before 221B, before Mrs Hudson and Lestrade and Molly and Sherlock – is like some old black and white movie. No colour – just various tones of grey. And then Sherlock exploded into John's life as though someone had used a Canon printer cartridge as a bomb and suddenly, not only was everything coloured, it was coloured so brightly that sometimes John's eyes hurt just to look at it.

With all that – all that rightness – how could John have guessed that meeting Sherlock was like getting hit with a small calibre bullet that only got bigger and bigger the longer it was left unattended, until finally – on the day that Mrs Hudson doesn't get shot and John clambers out of a taxi outside St Barts only to look up and see his closest, best, most beloved friend standing on the edge of the bloody roof – the damn thing's grown so much that it's like it's morphed into a bloody bazooka round, and it's pressed up against the skin next to John's spine, just ready and waiting to explode out of his back and leave a devastating mess of blood and heartbreak behind.

And sure enough, that's exactly what happens.

The detective jumps, the doctor screams, and the bullet that is Sherlock Holmes rips and tears and shreds its way out of John's back, and for the first time since it lodged in his ribs John becomes aware of it, and – more to the point – the gaping, ragged tunnel it's left through the middle of his chest and the giant cavity at his back where once he'd had skin and bone and muscle but where now he only has an empty, bloody, agonising hole.

He thinks he might have walked (staggered) forward. Later, when Lestrade's talking to him in low tones and trying to work out what happened, he can barely remember what occurred in between Sherlock jumping and John finding himself sitting on a bench down the road from the landing point with his head between his knees, the taste of vomit on his tongue and Lestrade's hand on his shoulder, but he knows that somewhere in the middle there he managed to get to Sherlock's side and check his pulse.

The pulse that Sherlock no longer has.

Holy shit, he can't breathe.

The remainder of that day passes in a foggy, oxygen-deprived blur. Everyone keeps trying to talk to him, but Lestrade sticks close to John and manages to fend most of them off.

Most of them. In a spectacular case of utterly awful timing, the DI gets called away for something apparently urgent. He grumbles under his breath then huffs an irritated sigh, and promises a mostly-unresponsive John that he'll be "back in a moment, alright, don't go anywhere." And Lestrade's only just vanished out of sight when Anderson and Donovan, of all people, spot John and make their way over to where he's sitting.

John's so lost in the fog and grief swirling around inside his head that he doesn't even notice them until they're right in front of him and one of them calls his name, and it's only then that he blinks and looks up. He stares blankly for a moment, recognition taking a second to hit, and when it does… well.

John doesn't know why they've come over – doesn't know if they're here to apologise or offer condolences or tell him "I told you so" or scoff at him to get the hell over it, the guy was a damn criminal, for heaven's sake – but he knows he's Not Happy To See Them.

They're the last damn people John wants to see right now, in fact. He'd take Moriarty over these two. Come to think of it, he'd take Moriarty over everyone except Sherlock right now, because even though John's never been prone to extreme violence, he knows he'd take a vicious (and slightly concerning) delight in being left alone with Jim Moriarty for a few hours with nothing but a small paring knife and a lot of imagination, but that aside, the fact remains that – out of all the people in the world who John wants or does not want to see right now, Anderson and Donovan (who always mocked Sherlock and threw insults at his back and who were the first to fall for Moriarty's twisted lies) are at the very, very bottom of the list.

"John," Anderson says, and John has no idea what the next words out of his mouth are going to be ("I'm sorry for your loss," or "Well, we all knew this was coming," or "Seriously? You're this upset about the freak?"), but he knows he doesn't want to hear them.

Anderson's nose makes a rather satisfying crack when John's fist smashes against it.

These two – Donovan, Anderson, and half of Scotland fucking Yard, damn it – they never understood, they never appreciated anything that Sherlock ever did for them; never took note of how many bad guys they caught because of Sherlock, never paused for a moment to wonder how many cold cases they'd have if it weren't for the Consulting Detective that they all treated with so much disdain and cruelty (and ok, it wasn't just one way, but Sherlock was never the one who threw the first barb, John can stand as witness to that much, at least). Donovan and Anderson both bought Moriarty's damn story and they didn't even hesitate and they should have known better damn it, because John's barely known Sherlock long at all, in the scheme of things, but they've known the detective for years and if John never believed Moriarty's lies then how the hell could anyone else possibly think that Sherlock would ever do any of what Moriarty invented?

(Really though, he shouldn't be surprised that they fell for Moriarty's game, because Donovan told John where she stood on the enigma that is (was) Sherlock Holmes the very day she met the detective's new flatmate. "One day we'll all be standing around a body," she'd said. "And Sherlock Holmes will be the one who put it there." And that turned out to be true, in the end, only the body that Sherlock Holmes put there is himself, and John can confidently say that no one saw that coming.)

Anderson's knocked flying by the force of John's blow and then John's on top of him, ready to throw some more punches (and he knows he has a damn good right hook when he wants to, and right now he wants to), but then Sally's got his arms and is pulling him back and John kind of wants to slam her in the face too, but never hit women is a code that John abides to even on the shittiest occasions, so he manages not to hit her, but only just.

She's got a pretty strong grip for her slight figure, but John's been a soldier in a warzone and he's got emotional devastation on his side and lending him strength, and if it weren't for Lestrade showing back up with a startled expression and leaping into the fray to help Donovan hold on to him, John probably would have managed to pull free and relaunch his attack.

Anderson's lying on the ground with a bloodied nose and a stunned expression and Donovan's yelling at John and Lestrade and Anderson and anyone who'll bloody listen, from the sound of it, and Lestrade's yelling at her to shut the hell up and he's trying to talk to John but John's a little bit too far past the edge of reason to hear any of what he's saying.

John's pretty sure he's yelling – at Anderson and Donovan, mostly, but also at all these people who are hanging around and gawking at the bloodied smear on the pavement where Sherlock's head hit the ground and at the photographers and paparazzi who are clamouring for a picture or a statement or the latest update on what happened here, and at every damn person who never saw the amazing man that Sherlock was and who only saw the stories that had the potential for selling newspapers and at the idiots who only ever believed the lies that the twisted, flawed media told them.

He's yelling at the lot of them and then all of a sudden he's not anymore, because his chest (not his lungs – John doesn't have lungs anymore, Sherlock took them back) is seizing and catching and he's damn well sobbing in the middle of a crowded street surrounded by his unofficial-colleagues with Lestrade and Donovan hanging on to one of his arms apiece and Anderson's still lying on the ground and bleeding. Stone pavers slams painfully into John's knees as they abruptly give out underneath him and he doesn't give a damn because it hurts, it hurts, it hurts, and Donovan lets go of his arm and he wraps it around his chest and keens at the agony because there's a gigantic hole in his back where the Sherlock-bullet ripped out of him and it bloody, damn well hurts.

He's gasping. The world is spinning around him in a mess of greys and blacks and he can't breathe – he can't bloody breathe, because Sherlock walked into John's life and gave him lungs and then he jumped back out of it and took the lungs away again and John might have known how to live without lungs once but he can't do it anymore, and Sherlock jumped off a damn building less than an hour ago and tore a great big massive hole in John when he did it, so now John's kneeling in the street sobbing breathlessly and dying from a hole that no one else can see.

Lestrade decides quickly that this isn't the place for this, and he stands and drags John with him and then starts bullying people out of the way, tugging John over to a police van sitting on the curb, and Donovan comes with them and adds her authority and sharp shoves to Lestrades to get the gawking onlookers to move out of the way, damn it, and maybe she and Anderson had been coming over to apologise, or maybe she's just been shocked by John's reaction, but either way she helps clear a path for them and opens the doors to the back of the van once they're close enough.

"The station, I think," Lestrade says, clambering in and pulling John with him. "Probably shouldn't make him go back to Baker Street just yet."

Donovan nods and closes the doors for them, and a minute later engine kicks to life, but John's oblivious to all of this because he still can't breathe. He knew how to do it once, but John can't breathe without lungs anymore and he's not only lung-less but he's got a giant crater in his back as well, because Sherlock was apparently a bullet that was tearing John to shreds from the inside without the doctor ever even noticing, and he can't breathe, can't breathe, can't breathe, oh, hell, he's going to die of oxygen deprivation because Sherlock gave him lungs and then took them away and he tore a great big hole in John as he did it and now John's sitting in the back of a police van bleeding out and dying of his exit wounds.

A heavy weight settles across John's shoulders and pulls at him, and he half-falls against Lestrade's side. The arm stays wrapped around his shoulders, and Greg is by far a more stable thing to lean against than the nothing John was leaning on before, so he stays where he is and doesn't even care that Greg's practically hugging him or that he's sobbing a bit wildly into the DI's unironed shirt, and apparently Lestrade doesn't care all that much either because he makes no moves to get out of the situation, so John stays put and Lestrade keeps his arm around him and says nothing as the World's Only Consulting Detective's closest friend falls to pieces in the back of a police van.

…

end

…

AN: I would love some feedback on how my first foray into the Sherlock fandom went. Now I'm off to do some more work on Driving in Cars With Strangers, which will be the next instalment in the Carbon Copy 'verse (no promises on when it'll be up, but it shouldn't be far away at all).