Fic: Let This River Flow; John/Sherlock, Dean/Castiel; NC-17 - Part 3/5
Title: Let This River Flow (3/5)
Crossover: Sherlock
Type: Slash, Gen
Rating: NC-17
Characters/Pairings: John/Sherlock, Dean/Castiel, Sam, Kevin, Charlie, Harry, Mycroft, OCs.
Warnings: Violence, sex, language.
Author's Note #1: Post-Reichenbach, and set post-S8 of Supernatural.
Author's Note #2: Title comes from ‘Let This River Flow’ by Soilwork.
Author's Note #3: Written for sncross_bigbang. Link to the gloriously wonderful artwork by the talented finnickodair can be found here. Thank you again, m’dear. ♥
Summary: In the year 2014, after an unknown disease decimates most of humankind, John and Sherlock are left doing their best to just stay alive, scraping out an existence in the quarantined city of London - until they stumble into the lives of two brothers and a fallen angel, who talk of the Devil as though he’s a real being, and who have a name - Croatoan - for the virus that’s torn the planet apart. From then on, John and Sherlock find themselves caught up in the epicenter of the battle, and it’s going to take everything they have to make it through with their humanity intact.
- - -
After that, it only takes a few hours for John to surmise that Dean is someone who, personal feelings notwithstanding, John would willingly follow into just about any battle.
He’s smart, he’s a phenomenal shot, he’s amazing with a knife, he knows how to fight these creatures, he knows how to direct a group of people, he’s clever enough to figure out that they’ll navigate the city with greater ease if he lets Sherlock weigh in on their routes - and while John still spends most of the day feeling like he’s about to be in the middle of a full-out brawl between Sherlock and Dean, it’s pretty damn obvious that the combination of Sherlock’s and Dean’s knowledge works to get them safely through the city until the sun starts going down. There are a few monster attacks - only knives, thankfully; no guns or explosions or anything particularly clever - but the five of them are easily able to fight their way through, Charlie and Cas and Dean carving through the creatures like this is something they do every day - and, for all that John knows, it could be - and by the time they take shelter on the third floor of an apartment building, John is counting himself lucky that Charlie and Cas and Dean had offered to come with them.
Of course, that doesn’t change the fact that they’re going to have to wait until morning to go any further - even though they’re close to Chesham Station - and John’s ready to scratch his skin off.
“Pacing a hole through the floor won’t make this place more secure, you know.”
Dean’s sitting on a chair in the corner, tilted back on two legs against the wall, gun on his lap and an almost pitying expression on his face, and John shoots him a glare before he keeps walking, doing his best to ignore everyone in the room. The window is boarded up, but there are enough cracks between the boards that they can rely on the dim moonlight to see by, and John’s eyes have long since adjusted. Charlie’s sitting on the grungy floor next to Dean, leaning up against the wall and polishing her knife, and Cas is staring out the window, gun held loosely in front of him, and Sherlock is keeping guard at the doorway, wrapped in his long coat and standing guard by the ragged couch that’s been pushed in front of the door, and John gets it, he does, gets that they can’t go any further tonight night, but god, Harry is out there, and he needs to find her.
“Dean.”
Cas’ voice is low and sharp - the first word he’s said, actually, since they left the prison - and his weapon is suddenly held a bit higher, and Dean goes very still, before he carefully, silently, lowers his chair back onto all four legs. Standing by the door, Sherlock’s already got his gun raised and ready, and John nearly jumps when there’s a hand on his arm - Charlie, he reminds himself - and then he’s keeping close to her, both of them moving towards the dim light that’s coming in through the window, until all of them save for Sherlock are peering out through the cracks at the large swarm of people who have gathered on the street. The moon isn’t completely full, but it’s still bright enough to see by, and John watches the group below them, distantly aware of Cas and Charlie on one side of him, and of Dean peering over his shoulder on the other.
“Son of a bitch.”
Dean breathes it low in the darkness, and John swallows, hard. That, there, is a large group of monsters - larger than any they’ve encountered so far - and while they don’t seem to be doing anything, at the moment - just seem to be congregating there - one false move, one flash of light or noise, could have them up the stairs and at the flat door in a dangerously short period of time.
“Okay, then. We’re definitely keeping watch in pairs tonight. Cas, how ’bout you and Charlie -”
Suddenly, though, Sherlock makes a low hissing sound from his spot by the door, and Dean falls silent. For a moment, there’s nothing - and then John hears it, too. The sound of footsteps in the hallway, way too fucking close, and he’s across the room and at Sherlock’s side as silently as he can be. Puts a hand on Sherlock’s arm, feels the way he’s nearly vibrating - and then Dean and Cas and Charlie are all there, too, spread out on either side of them, and John spares a moment to thank his eyes for starting to adjust, because that means he can see the way Dean raises his gun, looks at all of them, and then holsters it again, making an obvious movement of pulling out a knife instead. It’s enough to make John grind his teeth together, but he gets it - with that group outside, the last goddamn thing they need is gunfire - and he does the same, each of the others following suit, until all five of them are standing there in the darkness, perfectly still, knives out and ready, and the room completely silent save for their soft breathing. John isn’t sure how long they stand there - long enough for the footsteps and murmuring in the hallway to come and go, the area outside their apartment gradually falling silent again - but by the time Dean lowers his knife again, John is aching from holding the same position for so long, and his muscles scream out their protest as he finally lets himself relax, Dean breathing out slow and calm beside him.
“I’ll take first watch with Sherlock. Everyone else get some rest.”
For a moment, John thinks about protesting - he’s not quite sure that Sherlock and Dean won’t kill each other before their watch is up - but Sherlock puts a hand on his arm, gently squeezes before he lets go again, and John takes the hint. Sheathes his knife and turns to cross to his sleeping bag - and then he’s on the floor, hitting the old linoleum, hard, as something - an explosion? - has the room shaking, sending Cas to his knees, too, and knocking Charlie off her feet beside him. It’s over quickly, and then John’s scrambling to get upright again, clinging to a chair and pulling himself up as Dean spits out a series of curses and climbs up from where he’s hit the floor, too, and John somehow makes it back across the room to Sherlock, kneels down beside him, even as Dean scrambles across the room, pulling himself up to stare out the window.
“Son of a bitch.”
Dean’s voice is a hiss, distant in the background, because Sherlock, all John can care about it is - but Sherlock is holding on tight to his hand, up on his knees, suddenly, unhurt, and John feels himself shudder from the pure fucking relief, can’t tear his eyes from Sherlock for a moment - and then Charlie groans, and John spins towards her even as she raises a hand in his direction.
“I’m fine, I’m - the others, are they -”
“We might have a problem.”
Dean’s voice sounds strained, and John takes a moment longer to stare at both Charlie and Sherlock, god, he needs more light than this, before the two of them are gone, across the room to join Dean by the window - and John spins around, where is Cas, finds him sitting upright but looking dazed, shaken, his eyes bright and wide in the dim moonlight, and John grits his teeth together as he kneels down beside him - is about to start looking for injuries when Dean is suddenly there, not quite pushing John out of the way, but not exactly making any apologies for his presence, either, and John - feels his chest tighten painfully as Dean leans in towards Cas and puts a hand on his cheek, gently turns Cas’ head so that they’re staring at each other, Dean’s face suddenly sliding into the most concerned expression John’s ever seen on the guy, and - wow. John is pretty sure he’s been seeing without observing again, because how the hell did he miss this?
“Hey. C’mon, Cas - talk to me. You good?”
“I - Dean -”
“C’mon, man, what hurts?”
“I - everything, but - I think - I believe I am just bruised - I -”
“Unless something’s bleeding or broken -”
Cas shakes his head at that, but he still looking more than a bit stunned, looks unsure even as he shakes his head, and Dean stares at him for a moment longer before he sighs and drops his hand to Cas’ shoulder for a moment, and then pulls away completely, turning to John as he does so.
“Army doctor, right?”
“I - yes.”
“Look him over for me?”
“I - of course, but what -”
“Croats are blowing up buildings. The apartment across the street’s all but gone.”
“Jesus.”
“Yeah. But we gotta sit tight. We go out there, we’re finished.”
John nods his agreement - tries to not think about the fact that they’re on the fifth floor of a building, with monsters using bombs just on the other side of the street - and takes a final look at where Dean has moved to join Sherlock and Charlie at the window, before he turns back to Cas, who seems to be looking a bit less dazed, thought his eyes are still wide as he stares at John.
“I’m gonna take the coat off. Alright?”
“I - I believe I am fine. I was just - shocked.”
“Perhaps, but - I’d feel a lot better -”
But Cas shakes his head sharply - suddenly stubborn, apparently - and John fights the urge to try to stop him as Cas pushes himself up onto his knees, and then stumbles up to his feet again, John rising with him, ready to catch him should he fall again. There’s a moment when he thinks that he will - Cas wavers for a second, visibly unsteady - and then he makes a frustrated sound and seems to square his shoulders and plant his feet more solidly beneath him, his face creasing into a scowl as he reaches out to put a hand on John’s shoulder, using him to stay completely upright.
“I hate this body.”
And that - that, there, is so completely unexpected that, for a long moment, John can do nothing but stare. Puts a steadying hand under Cas’ elbow, at least, even as he tries to figure out what the hell Cas means by that - but then Cas is pushing himself away, standing on his own, and all John can do is blink as Cas scowls a little harder and crosses the room, still visibly shaky, to where Dean is. Stands under his own power for a moment before he leans against Dean, and Dean’s arm sneaks behind him to wrap around his waist, holding him steady - and John swallows, hard, and wonders, again, how he missed it with the two of them. Wonders what the hell Cas had meant, and wonders who the hell these people are, even, and wonders, for a moment, how he and Sherlock ever even ended up here in the first place. How this insanity ever became their lives.
“So what do we do, then?”
Charlie’s voice is barely audible, even in the silent room, and, from where he’s still standing in the middle of the room, John watches as Dean stares at her for a moment, and then glances sidelong at Cas, who’s still shaky and unsteady and pressed up close against him, and then turns back to the window, the sound of a cheering and hooting making it up from the street below.
“We stay put. You and I take first watch. The rest of you - get some sleep, alright? If we’re going to that damn subway tomorrow, then we’ve all gotta be as rested as we possibly can be.”
Dean’s voice seems to slide into exhausted, even as he says it, and John swallows hard, and tries to not think of Harry, out there, somewhere, with those monsters crawling around on the streets below. Glances down at his sleeping bag - knows damn well that he’s way too wired to think of sleeping - but then Sherlock’s moved to stand beside him, close and warm in the dim light, and when a hand closes around his wrist, John lets himself be tugged until he’s on the floor and sliding into the sleeping bag, Sherlock doing the same with his, and then pressing up against him, arms sliding around him from behind to pull him in close against Sherlock’s chest. John goes still for a moment - hadn’t expected such obvious affection, given that they’re not alone in the room - but Sherlock just tightens his grip, gently pulling him closer, and John feels himself start to relax, even as something inside him begins to ache in a way that has nothing to do with Harry being missing, and everything to do with the man pressed up against him. Here they are, trapped in yet another shit flat in the middle of an infested city, and Sherlock shouldn’t even be here.
“Stop thinking.”
“This from you?”
“You need to rest.”
“Again, from the man who deems sleep to be a waste of -”
“The better rested you are, the greater the chances of finding your sister.”
It’s still not a promise that they will, in fact, find her, but John hears the truth there - knows that Sherlock is right - and he manages a nod, before closing his eyes and doing his best to ignore the sound of whooping and hollering that’s making its way up from the streets below. The horrible sounds are enough to get all twisted up inside him, and he pushes himself closer to Sherlock, closes his eyes a bit tighter, and takes whatever comfort he can from the sound and feel of Sherlock breathing against him, as Sherlock tightens his arms around him and just holds on tight.
- - -
The next morning, by the time they’ve snuck out of the flat - the streets had mercifully emptied sometime around dawn - and made it to within viewing distance of the station, it’s pouring rain, and John is soaked straight through. Silently curses his useless cardigan, and then blinks through the water as Dean presses up against the brick wall beside him, looking just as soaked and miserable.
“Alright. What’s she even look like, anyway?”
Dean’s voice is low beneath the pounding of the rain, and John glances around to make sure that everyone is within hearing distance. Sherlock’s right beside him, of course, and Charlie and Cas are next in line, their weapons ready and their expressions set, even in the driving rain, and John feels an unexpected wave of fondness sweep through him; a sudden surge of gratitude that makes his throat too tight. Has to swallow hard and clear his throat before he can make words happen.
“About as tall as Charlie. Brown eyes, brown curls. Broad shoulders, a few freckles - um -”
“I was on duty when she left. She was wearing a black jacket and blue jeans.”
Charlie’s voice cuts in, sounding almost a little hopeful, and John feels his mouth twitch a smile in her direction, because - yeah, that’s definitely good information to have. She smiles back at him, hesitantly - and, god, it’s not her fault that Harry is here, not really; and John needs to keep that in mind, needs to find Harry first and then make peace with Charlie afterwards - and then Dean’s nodding beside him, and raising his knife a bit higher, eyes going to the station entrance. There are no monsters in the space between them and the doors, thankfully, and while John knows that it’s probably futile to hope that the station is deserted, too, it’s still a rather nice idea
“Alright. Keep it quiet. No guns, unless absolutely necessary, and no breaking formation, period. We stick together, end of story, no matter what happens. If one of us goes down, we all stop -”
“You say that as though it’s something you actually have to say.”
“Yeah, well -”
“Come on, Dean. All the Croats in the world couldn’t drag you and Cas apart, and I’m guessing that Sherlock and John here aren’t going anywhere without each other, so. You really think I’d leave your sorry ass behind?”
“I’ll have you know that there’s nothing sorry about my ass.”
Dean’s voice sounds a little bit unsteady, though, for all that he and Charlie are suddenly grinning at each other through the rain, and John breathes through that wave of fondness again. Finds himself leaning back against Sherlock, for a moment - feels Sherlock press a soft kiss against the back of his neck, warm and comforting in the cold rain, and more than enough to make John go all shaky inside - and then Dean’s expression settles again, and he makes eye contact with each of them before he speaks, tightening his grip on the large knife in his hand.
“Alright. Charlie up front with me, Cas in the middle, and John and Sherlock at the back. We check the station first, and if she’s not there, then we start banging down nearby doors. Deal?”
John nods - is aware of everyone else doing the same - and then Dean turns back to the station, and Charlie slides around John to stand beside Dean, even as Cas switches places with John and Sherlock, putting them at the rear and himself in the middle - and then Dean visibly steadies himself, takes a deep breath, and moves away from the building. They’re not moving at a run, exactly - which John is thankful for, as he has no desire to run headlong into a nest of monsters - but it’s a damn close thing, and they make it to the doors quickly enough, not encountering any resistance along the way. Dean and Charlie go in first, after Dean peers through one of the broken windows, and John and Sherlock watch the area behind them until they’re all inside, and -
Wow.
Whatever had once existed of the station, there’s barely anything left now. The building is crumbling - literally, the walls are falling down, and several pillars have smashed to the floor - and there’s an old vending machine lying on its side, crumpled there in a way that looks almost sad. On the far side of the room, where the escalators were once located, there’s a giant hole in the floor - and, as far as John can see, the entire upper level seems to be deserted. It’s unexpected enough to make him frown - it’s not like he wants to be fighting monsters, but they should have hit some kind of resistance by now - and when he glances over at Sherlock, it’s to find him looking just as perplexed. Nobody says a word, though - they simply follow Dean as he hesitates at the door, and then leads them along the wall to where the escalators once were - and then they’re staring down at the dark lower level, still accessible by the twisted remains of an old staircase; and of all the crazy ideas that John has contemplated lately, the notion of going down into the darkness of an old tube station is pretty high up there on the list of potentially bad plans.
“Alright, mister genius. Got any plans beyond just charging straight in?”
Dean’s voice is barely audible, even in the silent room, his knife raised a little higher in his hand as he peers down the stairs, and Sherlock scowls at the entire situation for a moment, his eyes sweeping across the remains of the station, before he goes back to contemplating the broken stairs.
“I dislike this.”
“Nobody likes it, buddy. So if you’ve got any brilliant ideas in that noggin of yours -”
“John and I go alone. You three stand guard here. I want to know that we have an exit.”
“You really sure that’s a good -”
“I have no desire to end up trapped on both ends.”
“Fair enough, but -”
“Dean.”
Cas’ voice is sharp from the building entrance, and everyone spins to face him as he seems to hesitate, for a moment, before he slowly takes a few steps away from the doorway, frowning, his gun firmly fixed on the crumbling entrance, and then - everything inside John freezes. Because Harry is hesitantly stepping through the doorway, soaking wet, blinking through the rain, covered in blood and dirt and bruises, with her hair everywhere and her eyes wide and alive -
John only realizes he’s jumped forward when someone - Sherlock, his voice sharp in John’s ear - grabs him, holds him back, and the only reason Sherlock’s nose isn’t broken is because John loves him. Snarls out something, at least, but Sherlock doesn’t let him go, and then Dean is there, holding his other arm, and John - makes himself go still, somehow, as much as he wants to claw at them both, because awareness is settling back in, and - Cas is standing even further away from Harry, now, still frowning, gun still trained on her, and there’s a reason for that, but John hates it.
“You can’t - John, we need to get her back, and test her blood - alright? Until then you can’t -”
John makes a noise he barely recognizes, but Sherlock must understand, somehow, because he lets go, Dean following suit more hesitantly - and John yanks himself away, seething, knowing he shouldn’t be, can’t help it, his eyes meeting Harry’s across the station and - god. His vision is damp, blurry around the edges, and it takes everything he has to keep his feet where they are. Can’t even manage to make words happen, just stares at Harry, until Harry takes a step closer, and John feels both Dean and Sherlock go tense beside him, and he holds up his hands, Harry going still again - the entire room seeming to go still until John somehow chokes out the words.
“Hi, Harry.”
For a moment, she just stares, still wide-eyed. Then, her expression seems to crumple a bit, and she lets out a gasping noise, rubbing a hand over her face for a moment before she seems to get herself together, her smile shaky and her eyes shiny with tears as she stares right back at him.
“Hi.”
And just - there is nothing more that John can seem to say. Makes another noise he doesn`t recognize, and then just gives up on speaking. Concentrates on keeping his knees locked underneath him. Everything’s too tight inside him and the world is too bright and all he can see is Harry, who smiles at him some more, bright and beautiful, and John actually cannot breathe.
“Touching as this all is, we gotta get somewhere safe.”
Dean’s voice is gruff, seems to come from far away - all John can see is Harry, smiling at him from across the room - but he does catch the way Sherlock nods his agreement, and then -
By the time John figures out the roof’s caved in, he’s already on his knees, and someone’s on top of him, shrieking and laughing and clawing at him. He tries to breathe, tries to twist away - can’t move; his attacker is much too heavy - and his knife is gone, his fingers are empty, and he can’t reach his gun - rears his head back and nearly knocks himself out when he makes contact, but there’s a crack that comes from bone breaking somewhere above him, and while his attacker is screaming, John’s able to squirm forward. Gets his hand around a chunk of concrete and spins onto his back, swings his arm with all the force he has, and sends the creature slumping sideways when the concrete makes contact with its temple. For a second, all he can do is gasp for air - and then he’s pushing the motionless body off and scrambling up to his knees. Dean and Charlie are back to back, their knives and bodies both covered in blood, and Sherlock is - two of the creatures are holding him, keeping him in place, and a third is landing punches, laughing and shrieking, and John scrambles to grab his knife from the floor, sinks it into the third monster before he realizes he’s moved. Aims right for a lung, sends the creature crashing to the ground, and then jumps back as one of the others leaps at him, yelling - but it’s one-on-one for both him and Sherlock, now, and John can’t ask for much more than that. Keeps out of reach as best as he can, until the creature slips on a piece of stone, and then John slashes its throat. Sends it down just in time to see Sherlock helping Charlie and Dean dispatch of a last few monsters and -
Harry.
The entrance is covered in chunks of concrete, the ceiling above blown out above the doorway area - and Cas and Harry are both surrounded by monsters, Harry shoved against a wall, her fists flying, and Cas a flurry of trench coat as he slices his way through the creatures, and John makes it across the room in seconds. Things blur out after that - stabbing, punching, kicking; whatever it takes - until he’s at Harry’s side, and she’s somehow gotten out her own knife, and they end up fighting nearly shoulder to shoulder. By the time all the creatures are dead, lying on the floor around them, John is panting, Harry’s holding herself up on his arm, Cas is leaning against the wall, Dean and Charlie are leaning on each other, Sherlock’s got that manic glow he always gets after emerging victorious against some dangerous foe, and every single one of them is covered in blood. For a moment, they all just stare at each other, panting and wide-eyed - and then there’s a shriek from the dark lower floor, and Dean’s hissing out a curse and bolting towards a side door.
“Come on!”
He barely yells it before he’s gone, Cas and Charlie tearing off after him, leaving Harry and Sherlock and John to do the same, a mad dash out into the rain - and John can hear the whoops and hollers starting up behind them, but he doesn’t dare turn to look. Takes hold of Harry’s hand - holds on tight to his knife with the other - and just runs for it, following Dean through the rain, Sherlock at his other side. The streets are soaked, and their footing is uneven, and the rain is damn near blinding - and John isn’t sure how long they run before Dean skids to a halt in front of them, in the middle of an intersection, looking every which way, even as Sherlock all but crashes into him, grabbing his arm and pulling when Dean tries to go left. Dean, to his credit, barely hesitates - simply stares at Sherlock through the rain, and then nods, even though it looks like his teeth are damn near grinding together - and John immediately breathes a bit easier when Sherlock slides into the lead. If anyone can get them somewhere safe alive, it’ll be Sherlock.
Time blurs out a bit, after that. John isn’t sure how long they run, knows his lungs are starting to ache, throat tasting of blood, by the time Sherlock veers into an alley, takes them off the main road and leaves everyone gasping for air as Sherlock skids to a stop and looks around him. For a second, nobody moves - and then Sherlock’s damn near climbing on top of a giant dumpster, Charlie and Dean right behind him, the three of them yanking it back with a screeching sound that makes John wince. He doesn’t have time to care, though - Dean and Charlie and Cas are already moving, scrambling over the edge and inside, and John waits until Harry’s in, too, before he follows, Sherlock sliding in last, everyone helping to lower the lid as silently as they can -
And then there’s nothing but the agonizingly loud sound of the rain against the metal above them. There are enough holes in the dumpster that some light can get in - they can see each other, at least, all pressed up against each other with barely enough room to breathe - but the bags of garbage are probably old enough to have things growing in them, and the stench is enough to bring John’s stomach up into his throat. He bites down hard against the rise of bile, holds his knife a little tighter, and squeezes past Harry to where Sherlock has an eye pressed against a hole in the dumpster. Wants to ask, but doesn’t dare speak. Waits until Sherlock looks at him and moves back, and John puts his eye against the hole, sucking in a deep breath - something he immediately regrets, when he gags on it - at the sight of the swarm that’s running past the alley entrance. There are dozens of them, easily, and John stays there until a good two minutes after the last one’s passed, before he pulls away and turns to face everyone. Charlie`s even paler than normal, and Dean’s looking angry enough to chew glass, and Harry’s wide-eyed in the dim light, and Cas is slumped against the garbage bags, eyes closed, looking exhausted -
But they’re alive. They’re all still alive, somehow, and Harry - Harry is alive and real and right in front of him, and nobody tries to stop him, this time, when he scrambles back across the dumpster; can’t breathe, yanks her in close, his throat going tight and scratchy at her disbelieving laugh, shaky in his ear, as she squeezes him tight; so tight he can’t get enough air into his lungs. Distantly, he can hear Sherlock and Dean talking, but it barely registers, everything around him just sliding away - holds on as tight as he can, and only lets go again when Harry’s no longer shaking, and when John can almost breathe again, and when the rain’s coming lighter against the metal above them. Holds her at arm’s length, though, and just kneels there and stares at her, takes in the bruises and the blood and dirty, still can’t seem to speak as she stares at him wide-eyed, her cheeks streaked with tears - until Dean stirs in his corner, sliding up onto his knees.
“Alright. That should be long enough. We need to keep moving.”
The words are still distant, though, until Harry squeezes his hand and nods at him, sucking in a shaky breath and managing to smile through her tears, even as Sherlock checks the hole in the dumpster one last time and Dean and Charlie push the lid up again; and then Harry climbs to her feet, tugging him up with her, and all of them slide out into the rain, standing there in the alley and all of them covered in blood and mud, reeking from the dumpster and already soaked straight through again. They’re still upright, though, and John has both Harry and Sherlock alive and in the same place, and he steadies his grip on his knife, meets Sherlock’s eyes for a moment, takes a world of comfort from that quick glance; and then he takes Harry’s hand again, and follows in silence as Sherlock pulls his coat tighter around him and leads them all back into the rain.
- - -
Chapter Four
Crossover: Sherlock
Type: Slash, Gen
Rating: NC-17
Characters/Pairings: John/Sherlock, Dean/Castiel, Sam, Kevin, Charlie, Harry, Mycroft, OCs.
Warnings: Violence, sex, language.
Author's Note #1: Post-Reichenbach, and set post-S8 of Supernatural.
Author's Note #2: Title comes from ‘Let This River Flow’ by Soilwork.
Author's Note #3: Written for sncross_bigbang. Link to the gloriously wonderful artwork by the talented finnickodair can be found here. Thank you again, m’dear. ♥
Summary: In the year 2014, after an unknown disease decimates most of humankind, John and Sherlock are left doing their best to just stay alive, scraping out an existence in the quarantined city of London - until they stumble into the lives of two brothers and a fallen angel, who talk of the Devil as though he’s a real being, and who have a name - Croatoan - for the virus that’s torn the planet apart. From then on, John and Sherlock find themselves caught up in the epicenter of the battle, and it’s going to take everything they have to make it through with their humanity intact.
- - -
After that, it only takes a few hours for John to surmise that Dean is someone who, personal feelings notwithstanding, John would willingly follow into just about any battle.
He’s smart, he’s a phenomenal shot, he’s amazing with a knife, he knows how to fight these creatures, he knows how to direct a group of people, he’s clever enough to figure out that they’ll navigate the city with greater ease if he lets Sherlock weigh in on their routes - and while John still spends most of the day feeling like he’s about to be in the middle of a full-out brawl between Sherlock and Dean, it’s pretty damn obvious that the combination of Sherlock’s and Dean’s knowledge works to get them safely through the city until the sun starts going down. There are a few monster attacks - only knives, thankfully; no guns or explosions or anything particularly clever - but the five of them are easily able to fight their way through, Charlie and Cas and Dean carving through the creatures like this is something they do every day - and, for all that John knows, it could be - and by the time they take shelter on the third floor of an apartment building, John is counting himself lucky that Charlie and Cas and Dean had offered to come with them.
Of course, that doesn’t change the fact that they’re going to have to wait until morning to go any further - even though they’re close to Chesham Station - and John’s ready to scratch his skin off.
“Pacing a hole through the floor won’t make this place more secure, you know.”
Dean’s sitting on a chair in the corner, tilted back on two legs against the wall, gun on his lap and an almost pitying expression on his face, and John shoots him a glare before he keeps walking, doing his best to ignore everyone in the room. The window is boarded up, but there are enough cracks between the boards that they can rely on the dim moonlight to see by, and John’s eyes have long since adjusted. Charlie’s sitting on the grungy floor next to Dean, leaning up against the wall and polishing her knife, and Cas is staring out the window, gun held loosely in front of him, and Sherlock is keeping guard at the doorway, wrapped in his long coat and standing guard by the ragged couch that’s been pushed in front of the door, and John gets it, he does, gets that they can’t go any further tonight night, but god, Harry is out there, and he needs to find her.
“Dean.”
Cas’ voice is low and sharp - the first word he’s said, actually, since they left the prison - and his weapon is suddenly held a bit higher, and Dean goes very still, before he carefully, silently, lowers his chair back onto all four legs. Standing by the door, Sherlock’s already got his gun raised and ready, and John nearly jumps when there’s a hand on his arm - Charlie, he reminds himself - and then he’s keeping close to her, both of them moving towards the dim light that’s coming in through the window, until all of them save for Sherlock are peering out through the cracks at the large swarm of people who have gathered on the street. The moon isn’t completely full, but it’s still bright enough to see by, and John watches the group below them, distantly aware of Cas and Charlie on one side of him, and of Dean peering over his shoulder on the other.
“Son of a bitch.”
Dean breathes it low in the darkness, and John swallows, hard. That, there, is a large group of monsters - larger than any they’ve encountered so far - and while they don’t seem to be doing anything, at the moment - just seem to be congregating there - one false move, one flash of light or noise, could have them up the stairs and at the flat door in a dangerously short period of time.
“Okay, then. We’re definitely keeping watch in pairs tonight. Cas, how ’bout you and Charlie -”
Suddenly, though, Sherlock makes a low hissing sound from his spot by the door, and Dean falls silent. For a moment, there’s nothing - and then John hears it, too. The sound of footsteps in the hallway, way too fucking close, and he’s across the room and at Sherlock’s side as silently as he can be. Puts a hand on Sherlock’s arm, feels the way he’s nearly vibrating - and then Dean and Cas and Charlie are all there, too, spread out on either side of them, and John spares a moment to thank his eyes for starting to adjust, because that means he can see the way Dean raises his gun, looks at all of them, and then holsters it again, making an obvious movement of pulling out a knife instead. It’s enough to make John grind his teeth together, but he gets it - with that group outside, the last goddamn thing they need is gunfire - and he does the same, each of the others following suit, until all five of them are standing there in the darkness, perfectly still, knives out and ready, and the room completely silent save for their soft breathing. John isn’t sure how long they stand there - long enough for the footsteps and murmuring in the hallway to come and go, the area outside their apartment gradually falling silent again - but by the time Dean lowers his knife again, John is aching from holding the same position for so long, and his muscles scream out their protest as he finally lets himself relax, Dean breathing out slow and calm beside him.
“I’ll take first watch with Sherlock. Everyone else get some rest.”
For a moment, John thinks about protesting - he’s not quite sure that Sherlock and Dean won’t kill each other before their watch is up - but Sherlock puts a hand on his arm, gently squeezes before he lets go again, and John takes the hint. Sheathes his knife and turns to cross to his sleeping bag - and then he’s on the floor, hitting the old linoleum, hard, as something - an explosion? - has the room shaking, sending Cas to his knees, too, and knocking Charlie off her feet beside him. It’s over quickly, and then John’s scrambling to get upright again, clinging to a chair and pulling himself up as Dean spits out a series of curses and climbs up from where he’s hit the floor, too, and John somehow makes it back across the room to Sherlock, kneels down beside him, even as Dean scrambles across the room, pulling himself up to stare out the window.
“Son of a bitch.”
Dean’s voice is a hiss, distant in the background, because Sherlock, all John can care about it is - but Sherlock is holding on tight to his hand, up on his knees, suddenly, unhurt, and John feels himself shudder from the pure fucking relief, can’t tear his eyes from Sherlock for a moment - and then Charlie groans, and John spins towards her even as she raises a hand in his direction.
“I’m fine, I’m - the others, are they -”
“We might have a problem.”
Dean’s voice sounds strained, and John takes a moment longer to stare at both Charlie and Sherlock, god, he needs more light than this, before the two of them are gone, across the room to join Dean by the window - and John spins around, where is Cas, finds him sitting upright but looking dazed, shaken, his eyes bright and wide in the dim moonlight, and John grits his teeth together as he kneels down beside him - is about to start looking for injuries when Dean is suddenly there, not quite pushing John out of the way, but not exactly making any apologies for his presence, either, and John - feels his chest tighten painfully as Dean leans in towards Cas and puts a hand on his cheek, gently turns Cas’ head so that they’re staring at each other, Dean’s face suddenly sliding into the most concerned expression John’s ever seen on the guy, and - wow. John is pretty sure he’s been seeing without observing again, because how the hell did he miss this?
“Hey. C’mon, Cas - talk to me. You good?”
“I - Dean -”
“C’mon, man, what hurts?”
“I - everything, but - I think - I believe I am just bruised - I -”
“Unless something’s bleeding or broken -”
Cas shakes his head at that, but he still looking more than a bit stunned, looks unsure even as he shakes his head, and Dean stares at him for a moment longer before he sighs and drops his hand to Cas’ shoulder for a moment, and then pulls away completely, turning to John as he does so.
“Army doctor, right?”
“I - yes.”
“Look him over for me?”
“I - of course, but what -”
“Croats are blowing up buildings. The apartment across the street’s all but gone.”
“Jesus.”
“Yeah. But we gotta sit tight. We go out there, we’re finished.”
John nods his agreement - tries to not think about the fact that they’re on the fifth floor of a building, with monsters using bombs just on the other side of the street - and takes a final look at where Dean has moved to join Sherlock and Charlie at the window, before he turns back to Cas, who seems to be looking a bit less dazed, thought his eyes are still wide as he stares at John.
“I’m gonna take the coat off. Alright?”
“I - I believe I am fine. I was just - shocked.”
“Perhaps, but - I’d feel a lot better -”
But Cas shakes his head sharply - suddenly stubborn, apparently - and John fights the urge to try to stop him as Cas pushes himself up onto his knees, and then stumbles up to his feet again, John rising with him, ready to catch him should he fall again. There’s a moment when he thinks that he will - Cas wavers for a second, visibly unsteady - and then he makes a frustrated sound and seems to square his shoulders and plant his feet more solidly beneath him, his face creasing into a scowl as he reaches out to put a hand on John’s shoulder, using him to stay completely upright.
“I hate this body.”
And that - that, there, is so completely unexpected that, for a long moment, John can do nothing but stare. Puts a steadying hand under Cas’ elbow, at least, even as he tries to figure out what the hell Cas means by that - but then Cas is pushing himself away, standing on his own, and all John can do is blink as Cas scowls a little harder and crosses the room, still visibly shaky, to where Dean is. Stands under his own power for a moment before he leans against Dean, and Dean’s arm sneaks behind him to wrap around his waist, holding him steady - and John swallows, hard, and wonders, again, how he missed it with the two of them. Wonders what the hell Cas had meant, and wonders who the hell these people are, even, and wonders, for a moment, how he and Sherlock ever even ended up here in the first place. How this insanity ever became their lives.
“So what do we do, then?”
Charlie’s voice is barely audible, even in the silent room, and, from where he’s still standing in the middle of the room, John watches as Dean stares at her for a moment, and then glances sidelong at Cas, who’s still shaky and unsteady and pressed up close against him, and then turns back to the window, the sound of a cheering and hooting making it up from the street below.
“We stay put. You and I take first watch. The rest of you - get some sleep, alright? If we’re going to that damn subway tomorrow, then we’ve all gotta be as rested as we possibly can be.”
Dean’s voice seems to slide into exhausted, even as he says it, and John swallows hard, and tries to not think of Harry, out there, somewhere, with those monsters crawling around on the streets below. Glances down at his sleeping bag - knows damn well that he’s way too wired to think of sleeping - but then Sherlock’s moved to stand beside him, close and warm in the dim light, and when a hand closes around his wrist, John lets himself be tugged until he’s on the floor and sliding into the sleeping bag, Sherlock doing the same with his, and then pressing up against him, arms sliding around him from behind to pull him in close against Sherlock’s chest. John goes still for a moment - hadn’t expected such obvious affection, given that they’re not alone in the room - but Sherlock just tightens his grip, gently pulling him closer, and John feels himself start to relax, even as something inside him begins to ache in a way that has nothing to do with Harry being missing, and everything to do with the man pressed up against him. Here they are, trapped in yet another shit flat in the middle of an infested city, and Sherlock shouldn’t even be here.
“Stop thinking.”
“This from you?”
“You need to rest.”
“Again, from the man who deems sleep to be a waste of -”
“The better rested you are, the greater the chances of finding your sister.”
It’s still not a promise that they will, in fact, find her, but John hears the truth there - knows that Sherlock is right - and he manages a nod, before closing his eyes and doing his best to ignore the sound of whooping and hollering that’s making its way up from the streets below. The horrible sounds are enough to get all twisted up inside him, and he pushes himself closer to Sherlock, closes his eyes a bit tighter, and takes whatever comfort he can from the sound and feel of Sherlock breathing against him, as Sherlock tightens his arms around him and just holds on tight.
- - -
The next morning, by the time they’ve snuck out of the flat - the streets had mercifully emptied sometime around dawn - and made it to within viewing distance of the station, it’s pouring rain, and John is soaked straight through. Silently curses his useless cardigan, and then blinks through the water as Dean presses up against the brick wall beside him, looking just as soaked and miserable.
“Alright. What’s she even look like, anyway?”
Dean’s voice is low beneath the pounding of the rain, and John glances around to make sure that everyone is within hearing distance. Sherlock’s right beside him, of course, and Charlie and Cas are next in line, their weapons ready and their expressions set, even in the driving rain, and John feels an unexpected wave of fondness sweep through him; a sudden surge of gratitude that makes his throat too tight. Has to swallow hard and clear his throat before he can make words happen.
“About as tall as Charlie. Brown eyes, brown curls. Broad shoulders, a few freckles - um -”
“I was on duty when she left. She was wearing a black jacket and blue jeans.”
Charlie’s voice cuts in, sounding almost a little hopeful, and John feels his mouth twitch a smile in her direction, because - yeah, that’s definitely good information to have. She smiles back at him, hesitantly - and, god, it’s not her fault that Harry is here, not really; and John needs to keep that in mind, needs to find Harry first and then make peace with Charlie afterwards - and then Dean’s nodding beside him, and raising his knife a bit higher, eyes going to the station entrance. There are no monsters in the space between them and the doors, thankfully, and while John knows that it’s probably futile to hope that the station is deserted, too, it’s still a rather nice idea
“Alright. Keep it quiet. No guns, unless absolutely necessary, and no breaking formation, period. We stick together, end of story, no matter what happens. If one of us goes down, we all stop -”
“You say that as though it’s something you actually have to say.”
“Yeah, well -”
“Come on, Dean. All the Croats in the world couldn’t drag you and Cas apart, and I’m guessing that Sherlock and John here aren’t going anywhere without each other, so. You really think I’d leave your sorry ass behind?”
“I’ll have you know that there’s nothing sorry about my ass.”
Dean’s voice sounds a little bit unsteady, though, for all that he and Charlie are suddenly grinning at each other through the rain, and John breathes through that wave of fondness again. Finds himself leaning back against Sherlock, for a moment - feels Sherlock press a soft kiss against the back of his neck, warm and comforting in the cold rain, and more than enough to make John go all shaky inside - and then Dean’s expression settles again, and he makes eye contact with each of them before he speaks, tightening his grip on the large knife in his hand.
“Alright. Charlie up front with me, Cas in the middle, and John and Sherlock at the back. We check the station first, and if she’s not there, then we start banging down nearby doors. Deal?”
John nods - is aware of everyone else doing the same - and then Dean turns back to the station, and Charlie slides around John to stand beside Dean, even as Cas switches places with John and Sherlock, putting them at the rear and himself in the middle - and then Dean visibly steadies himself, takes a deep breath, and moves away from the building. They’re not moving at a run, exactly - which John is thankful for, as he has no desire to run headlong into a nest of monsters - but it’s a damn close thing, and they make it to the doors quickly enough, not encountering any resistance along the way. Dean and Charlie go in first, after Dean peers through one of the broken windows, and John and Sherlock watch the area behind them until they’re all inside, and -
Wow.
Whatever had once existed of the station, there’s barely anything left now. The building is crumbling - literally, the walls are falling down, and several pillars have smashed to the floor - and there’s an old vending machine lying on its side, crumpled there in a way that looks almost sad. On the far side of the room, where the escalators were once located, there’s a giant hole in the floor - and, as far as John can see, the entire upper level seems to be deserted. It’s unexpected enough to make him frown - it’s not like he wants to be fighting monsters, but they should have hit some kind of resistance by now - and when he glances over at Sherlock, it’s to find him looking just as perplexed. Nobody says a word, though - they simply follow Dean as he hesitates at the door, and then leads them along the wall to where the escalators once were - and then they’re staring down at the dark lower level, still accessible by the twisted remains of an old staircase; and of all the crazy ideas that John has contemplated lately, the notion of going down into the darkness of an old tube station is pretty high up there on the list of potentially bad plans.
“Alright, mister genius. Got any plans beyond just charging straight in?”
Dean’s voice is barely audible, even in the silent room, his knife raised a little higher in his hand as he peers down the stairs, and Sherlock scowls at the entire situation for a moment, his eyes sweeping across the remains of the station, before he goes back to contemplating the broken stairs.
“I dislike this.”
“Nobody likes it, buddy. So if you’ve got any brilliant ideas in that noggin of yours -”
“John and I go alone. You three stand guard here. I want to know that we have an exit.”
“You really sure that’s a good -”
“I have no desire to end up trapped on both ends.”
“Fair enough, but -”
“Dean.”
Cas’ voice is sharp from the building entrance, and everyone spins to face him as he seems to hesitate, for a moment, before he slowly takes a few steps away from the doorway, frowning, his gun firmly fixed on the crumbling entrance, and then - everything inside John freezes. Because Harry is hesitantly stepping through the doorway, soaking wet, blinking through the rain, covered in blood and dirt and bruises, with her hair everywhere and her eyes wide and alive -
John only realizes he’s jumped forward when someone - Sherlock, his voice sharp in John’s ear - grabs him, holds him back, and the only reason Sherlock’s nose isn’t broken is because John loves him. Snarls out something, at least, but Sherlock doesn’t let him go, and then Dean is there, holding his other arm, and John - makes himself go still, somehow, as much as he wants to claw at them both, because awareness is settling back in, and - Cas is standing even further away from Harry, now, still frowning, gun still trained on her, and there’s a reason for that, but John hates it.
“You can’t - John, we need to get her back, and test her blood - alright? Until then you can’t -”
John makes a noise he barely recognizes, but Sherlock must understand, somehow, because he lets go, Dean following suit more hesitantly - and John yanks himself away, seething, knowing he shouldn’t be, can’t help it, his eyes meeting Harry’s across the station and - god. His vision is damp, blurry around the edges, and it takes everything he has to keep his feet where they are. Can’t even manage to make words happen, just stares at Harry, until Harry takes a step closer, and John feels both Dean and Sherlock go tense beside him, and he holds up his hands, Harry going still again - the entire room seeming to go still until John somehow chokes out the words.
“Hi, Harry.”
For a moment, she just stares, still wide-eyed. Then, her expression seems to crumple a bit, and she lets out a gasping noise, rubbing a hand over her face for a moment before she seems to get herself together, her smile shaky and her eyes shiny with tears as she stares right back at him.
“Hi.”
And just - there is nothing more that John can seem to say. Makes another noise he doesn`t recognize, and then just gives up on speaking. Concentrates on keeping his knees locked underneath him. Everything’s too tight inside him and the world is too bright and all he can see is Harry, who smiles at him some more, bright and beautiful, and John actually cannot breathe.
“Touching as this all is, we gotta get somewhere safe.”
Dean’s voice is gruff, seems to come from far away - all John can see is Harry, smiling at him from across the room - but he does catch the way Sherlock nods his agreement, and then -
By the time John figures out the roof’s caved in, he’s already on his knees, and someone’s on top of him, shrieking and laughing and clawing at him. He tries to breathe, tries to twist away - can’t move; his attacker is much too heavy - and his knife is gone, his fingers are empty, and he can’t reach his gun - rears his head back and nearly knocks himself out when he makes contact, but there’s a crack that comes from bone breaking somewhere above him, and while his attacker is screaming, John’s able to squirm forward. Gets his hand around a chunk of concrete and spins onto his back, swings his arm with all the force he has, and sends the creature slumping sideways when the concrete makes contact with its temple. For a second, all he can do is gasp for air - and then he’s pushing the motionless body off and scrambling up to his knees. Dean and Charlie are back to back, their knives and bodies both covered in blood, and Sherlock is - two of the creatures are holding him, keeping him in place, and a third is landing punches, laughing and shrieking, and John scrambles to grab his knife from the floor, sinks it into the third monster before he realizes he’s moved. Aims right for a lung, sends the creature crashing to the ground, and then jumps back as one of the others leaps at him, yelling - but it’s one-on-one for both him and Sherlock, now, and John can’t ask for much more than that. Keeps out of reach as best as he can, until the creature slips on a piece of stone, and then John slashes its throat. Sends it down just in time to see Sherlock helping Charlie and Dean dispatch of a last few monsters and -
Harry.
The entrance is covered in chunks of concrete, the ceiling above blown out above the doorway area - and Cas and Harry are both surrounded by monsters, Harry shoved against a wall, her fists flying, and Cas a flurry of trench coat as he slices his way through the creatures, and John makes it across the room in seconds. Things blur out after that - stabbing, punching, kicking; whatever it takes - until he’s at Harry’s side, and she’s somehow gotten out her own knife, and they end up fighting nearly shoulder to shoulder. By the time all the creatures are dead, lying on the floor around them, John is panting, Harry’s holding herself up on his arm, Cas is leaning against the wall, Dean and Charlie are leaning on each other, Sherlock’s got that manic glow he always gets after emerging victorious against some dangerous foe, and every single one of them is covered in blood. For a moment, they all just stare at each other, panting and wide-eyed - and then there’s a shriek from the dark lower floor, and Dean’s hissing out a curse and bolting towards a side door.
“Come on!”
He barely yells it before he’s gone, Cas and Charlie tearing off after him, leaving Harry and Sherlock and John to do the same, a mad dash out into the rain - and John can hear the whoops and hollers starting up behind them, but he doesn’t dare turn to look. Takes hold of Harry’s hand - holds on tight to his knife with the other - and just runs for it, following Dean through the rain, Sherlock at his other side. The streets are soaked, and their footing is uneven, and the rain is damn near blinding - and John isn’t sure how long they run before Dean skids to a halt in front of them, in the middle of an intersection, looking every which way, even as Sherlock all but crashes into him, grabbing his arm and pulling when Dean tries to go left. Dean, to his credit, barely hesitates - simply stares at Sherlock through the rain, and then nods, even though it looks like his teeth are damn near grinding together - and John immediately breathes a bit easier when Sherlock slides into the lead. If anyone can get them somewhere safe alive, it’ll be Sherlock.
Time blurs out a bit, after that. John isn’t sure how long they run, knows his lungs are starting to ache, throat tasting of blood, by the time Sherlock veers into an alley, takes them off the main road and leaves everyone gasping for air as Sherlock skids to a stop and looks around him. For a second, nobody moves - and then Sherlock’s damn near climbing on top of a giant dumpster, Charlie and Dean right behind him, the three of them yanking it back with a screeching sound that makes John wince. He doesn’t have time to care, though - Dean and Charlie and Cas are already moving, scrambling over the edge and inside, and John waits until Harry’s in, too, before he follows, Sherlock sliding in last, everyone helping to lower the lid as silently as they can -
And then there’s nothing but the agonizingly loud sound of the rain against the metal above them. There are enough holes in the dumpster that some light can get in - they can see each other, at least, all pressed up against each other with barely enough room to breathe - but the bags of garbage are probably old enough to have things growing in them, and the stench is enough to bring John’s stomach up into his throat. He bites down hard against the rise of bile, holds his knife a little tighter, and squeezes past Harry to where Sherlock has an eye pressed against a hole in the dumpster. Wants to ask, but doesn’t dare speak. Waits until Sherlock looks at him and moves back, and John puts his eye against the hole, sucking in a deep breath - something he immediately regrets, when he gags on it - at the sight of the swarm that’s running past the alley entrance. There are dozens of them, easily, and John stays there until a good two minutes after the last one’s passed, before he pulls away and turns to face everyone. Charlie`s even paler than normal, and Dean’s looking angry enough to chew glass, and Harry’s wide-eyed in the dim light, and Cas is slumped against the garbage bags, eyes closed, looking exhausted -
But they’re alive. They’re all still alive, somehow, and Harry - Harry is alive and real and right in front of him, and nobody tries to stop him, this time, when he scrambles back across the dumpster; can’t breathe, yanks her in close, his throat going tight and scratchy at her disbelieving laugh, shaky in his ear, as she squeezes him tight; so tight he can’t get enough air into his lungs. Distantly, he can hear Sherlock and Dean talking, but it barely registers, everything around him just sliding away - holds on as tight as he can, and only lets go again when Harry’s no longer shaking, and when John can almost breathe again, and when the rain’s coming lighter against the metal above them. Holds her at arm’s length, though, and just kneels there and stares at her, takes in the bruises and the blood and dirty, still can’t seem to speak as she stares at him wide-eyed, her cheeks streaked with tears - until Dean stirs in his corner, sliding up onto his knees.
“Alright. That should be long enough. We need to keep moving.”
The words are still distant, though, until Harry squeezes his hand and nods at him, sucking in a shaky breath and managing to smile through her tears, even as Sherlock checks the hole in the dumpster one last time and Dean and Charlie push the lid up again; and then Harry climbs to her feet, tugging him up with her, and all of them slide out into the rain, standing there in the alley and all of them covered in blood and mud, reeking from the dumpster and already soaked straight through again. They’re still upright, though, and John has both Harry and Sherlock alive and in the same place, and he steadies his grip on his knife, meets Sherlock’s eyes for a moment, takes a world of comfort from that quick glance; and then he takes Harry’s hand again, and follows in silence as Sherlock pulls his coat tighter around him and leads them all back into the rain.
- - -
Chapter Four