He can't go back to the flat. He really can't.

John stands on the pavement outside the cemetery after Mrs. Hudson gets in a cab alone, gripping his phone with white-knuckled hands and wondering if maybe he could make himself do it - if he could hail a cab and tell them 221 Baker Street, if he could just go home, up the stairs and round the corner, and make himself walk through the door even though Sherlock isn't there, and he won't ever be there again.

But he can't do it, in the end. So he calls Harry, who is mercifully sober. Her voice is kind - too kind, almost, soft in a way that doesn't suit her - and she offers him a place to stay, if he really needs it.

John doesn't want to need it, but he does. Mrs. Hudson brings him some of his things and Harry sets him up in her guest room. She makes him tea and sprawls out next to him, her feet in his lap the way she's always done when the two of them share a couch. They watch bad telly and talk companionably, more friendly than they've been in years, until three in the morning. It almost feels like being a kid again, except for the way they don't talk about anything that matters - about the bottle of rum he saw in Harry's kitchen cabinet, or about Sherlock, or about the box of Clara's things that's still sitting in the guest room, unclaimed.

They go on not talking about anything important for four weeks, and John feels like he's in limbo, or Purgatory, somewhere between life and whatever comes afterwards.

John has just gotten settled in one of Harry's overstuffed chairs, a steaming mug of tea halfway to his mouth, when there's a knock on the door.

Typical. He allows himself a bit of angry muttering under his breath as he pads over to the door, stocking feet sliding across Harry's polished wood entryway.

The man at the door is quite possibly one of the strangest people John's ever seen. This, coming from a man who lived with Sherlock Holmes for nearly two years, is saying something. He's young, with floppy brown hair and a very wide face, but his clothes make him look like a mad cross between colourblind pensioner and panto performer - out-of-date dress shirt and vest, red bow tie, long impractical coat. The smile that's spread across his face when John opens the door is broad and real, quite clearly prepared to charm someone into submission, but it quickly fades into genuine confusion as the other man realizes just who's opened the door.

"You're not Clara." The man in the bow tie says; disapproving, as if the lack of Clara is John's fault entirely.

"Er, no." John consciously allows his irritation to bleed into his voice. "No, I'm not."

The look of confusion on the other man's face seems very at home there, as if it's an expression he wears extremely often. "But this is Clara's house."

"It hasn't been for a while, mate." John makes to shut the door, but a firm hand planted in the middle of it stops him.

"I'm sorry, you're sure?" The odd man's smile is back, if dimmed considerably. John has the distinct feeling that he's being handled. "Clara Oswin Oswald? I have it on good authority that this-" he gestures vaguely at Harry's building- "is where she lives."

John sighs. His tea is getting cold, and it's freezing out here on the stoop. "Well, I'm not sure that Clara's middle name is Oswin, but I'm very sure she doesn't live here anymore. You tend to move out, when you get divorced."

The man brightens. Odd, that. "Brilliant! Nothing better for finding someone than a ex-husband. Always say you've given up, but you never really do."

A little strangled noise makes its way out of John's throat. He's not proud. "What? No, not me. My sister. My sister is Clara's ex. And she's at work." He can't imagine why anyone who knows Clara would think she still lives here. It's not as though she and Harry broke up amicably.

"Oh." Thin brows crinkle together, and the man pauses for a moment before asking "I don't suppose you'd know where Clara lives now?"

John's answer is the satisfying thud of the door slamming closed, and for a moment, it seems as though that's that. He ambles back across the slippery wooden floor and onto the carpet in the living room. He settles back down in the armchair and turns on the telly. Then, when his mouth is just inches from the mug of tragically lukewarm tea, the bell goes again. And again, and again.

This time, he wrenches the door open with a bit more force than is strictly necessary, and grinds out a "Yes?" in an icy tone he thinks Sherlock would have approved of.

It's the man with the bow tie, which is unsurprising but irritating all the same. "I'm sorry, but could you tell me what year it is?"

Somewhere in between John opening the door the second time and him saying "What?" when the stranger asked for a refresher on the bloody year, the man in the bow tie has waltzed right past him, through the entryway and into the living room. He's pulled something sleek and metal out of his coat pocket, and is waving it about at anything and everything. It makes an odd, high-pitched whirring sound and glows green at the tip. John can't decide whether it looks more like something out of science fiction or like something Sherlock built during one of his mad forays into the mechanical sciences.

"You can't just wander into people's houses like this." John follows the other man into the living room, where he's inspecting Harry's small photo collection – a haphazard group of snapshots, tacked to the wall across from the telly. There are conspicuous holes in the collage where photos of her and Clara have been removed, a messy and inelegant metaphor for his sister's life.

"Nonsense. Been doing it for ages."

John has to admit that he, too, is more than practiced in this particular art. Sherlock's theoretical respect for the law never did seem to extend to trespassing, or to breaking and entering. "Still, you can't-" He boggles, a little bit - not because this situation bothers him particularly, but because it doesn't. Nothing really seems to, not anymore. "What are you doing?"

The man doesn't answer, just whips out his odd little device and makes for the back hallway, towards Harry's bedroom. The high-pitched humming and green light is back, accompanied by nonsensical muttering from the stranger. The man talks so quickly that John only catches one word in ten, but the ones he does catch – impossible, temporal rift, bio-replication – are not at all encouraging.

"Who are you?" John manages to get out eventually. It sounds a little more high-pitched than he'd like, strangled as it is by a heady mix of sheer confusion and tentative curiosity.

That – that makes the other man stop, and he turns to face John with a small little smile as he says, "I'm the Doctor."

After John's finally got the Doctor – and what sort of bloody name is that – to put his little device away and stop touching everything for five seconds, he tries to start the questions again.

"So, why are you here?"

"I told you, I'm looking for Clara."

"Clara, my ex-sister-in-law." The Doctor nods. "Why?"

The Doctor shuffles in place a bit, uncomfortably. It makes him look all of five years old, and the action paired with his daft wardrobe produces an effect so ridiculous that John has to suppress laughter. "It's…rather difficult to explain."

That's when all of the lights go out, and a soft buzzing hum, almost like the sound of a swarm of bees approaching, falls over the flat.

John reaches for something to grab onto in the darkness, and he fumbles a bit before finding the wall, grounding himself against it. Then the high-pitched whirring comes back, the sound warring unpleasantly with the omnipresent hum that accompanied the darkness. John can feel his eardrums start to ache. Then, suddenly, the Doctor's face comes into view, illuminated by soft green light.

"What the hell is going on?" John grinds out. "Did you do that?"

"No." The Doctor says slowly, looking sheepish. "I may have, er, irritated some people on my way here, and I thought – well, I assumed, perfectly reasonable assumption to make – that they wouldn't be able to follow me to twenty-first century London, but apparently they've taken advantage of the residual temporal signature that the TARDIS leaves behind, drafting through the Vortex, if you will–"

"Just–" John interrupts, before the Doctor can say anything else that makes no sense. "Short version. What do we do?"

John feels a hand close over his, where it's pressed to the wall. "I'm going to ask you to take my hand. Then this light–" the green light dances about a bit, as though the Doctor is waving his little metal stick back and forth– "is going to go out, and I'm going to run." The other man's face is deadly serious now, and John wonders how he ever could have thought he looked like a child. "And I need you to run with me."

It feels like that first day with Sherlock, like saying God yes, like feeling his heart skip a beat with excitement at could be dangerous.

John takes the Doctor's hand and runs.

The Doctor runs very, very fast, but not as fast as Sherlock. John is proud of the fact that he has no trouble keeping up as they dash out of Harry's flat via the back door, tearing into the alley and round the corner, where there's a – is that a police box? – tucked up against the side of the building.

The Doctor drags John up to the box and makes to open the door, at which point John wrenches his hand away and says, "Wait!"

"What?" The Doctor snaps.

"Where are we going? Are we seriously going to hide – the both of us, we'd barely fit – in a police box? And for that matter, why is there a police box on this street? This isn't the sixties, and this was not here yesterday!"

John means to keep going with his long list of questions – at the top of it what the hell are we running from, exactly – but the Doctor gets there first. Not, of course, that what he says makes any sense, because apparently that's just not the sort of day John is having.

"There are a whole lot of very, very cross electro-insectoid creatures about to descend upon us, and as they've got a distressingly excellent sense of smell for a species with no noses, they've already noticed you and decided that, since you're with me, you'd make an excellent side dish to go with Doctor à la King."

John allows himself to gape, just a little bit. "Did you really just use aliens as your excuse?"

The Doctor huffs, clearly annoyed. John opens his mouth to assure him that the feeling is quite mutual when the humming sound, the one that had disappeared when they left Harry's flat – or maybe just quieted a bit; John can't remember, between the rush of adrenaline and the pounding of his heart – comes back. It's louder than before, and moving, if the way it's getting even louder and louder is any indication. The Doctor takes out his little device again and brandishes it towards the corner they've just come round, as if it's a gun or a sword and there's about to be a duel.

Then an absolutely giant – bug-man-thing, John's mind can barely process it, just throws together a few words that might be used to describe parts of the creature – comes around the corner, and the Doctor's metal bit glows and whirs. One of the lamps attached to the side of the building sparks and explodes, coming free from the wall and falling into the path of the…thing. The high-pitched humming turns into even higher-pitched screeching, and then the Doctor pushes open the door of the police box and hauls John inside. He fully expects to be pushed up close against the other man in the box's confined space, so when he turns around to find that the Doctor has, in fact, dashed off into the middle of a dimly lit, metal-lined room that is absolutely too big to be the inside of the police box, he's – well.

Surprised is a bit of an understatement.

As the Doctor fiddles with the console in the middle of the room – a stark metal apparatus with a glowing bluish-green column at the middle, currently humming softly and making a peculiar whooshing sound – he leads John through the whole yes, it's bigger on the inside bit and past the time and relative dimension in space madness before he gets to the most immediately relevant question.

"Wait, so what happened to the giant…bug things? Won't they be…rampaging? Going after innocents? That's what the aliens always do in the films."

"Films." The Doctor says this with disgust, like it's a swear word. "The Fferiyon are a perfectly peaceable species. Mostly. They've got no quarrel with anyone on Earth. Just me. They'll leave as soon as they realize we've gone, and if we hang about in the Vortex for a while, they won't be able to track the TARDIS like they did last time." He flips a few knobs on the console and the column goes quiet – not quite silent, but muted, a background noise that's oddly comforting despite its otherworldly tone. "Besides, this was all just a misunderstanding, really. How was I supposed to know that you're not allowed to park on the fifth moon of Atrilon during the fall solstice?"

John shakes his head. "Wait. You pulled me out of my sister's flat – in my socks, I might add – and got me chased by a horde of alien bugs because you were ducking a parking ticket?"

The Doctor, to his credit, at least has the decency to look a little sheepish.

The Vortex – which is, according to the Doctor, sort of an in-between place in time and space, except not like that at all really; John gave up on getting an explanation after the third time the Doctor contradicted himself – is where they're apparently going to have to stay for a while. The Fferiyon version of a paying a parking ticket apparently involves a spot of ritual sacrifice, so that's right out.

John introduces himself, properly, because his mum raised him with some manners, and the Doctor goes back to looking like a child, delighted as can be, when he finds out John's a doctor. He lets him look round the rest of the police box – its proper name is apparently the TARDIS – and John finds the kitchen located conveniently off the main room. There's a kettle already on, and mugs aren't difficult to find, and all the madness of this is just so much easier to process with a cuppa.

"You're taking all of this shockingly well." the Doctor comments, when John comes back to the main room to present the man with a mug of his own, which he accepts. He's shed his long, outdated coat and rolled up his sleeves, which has the effect of making his red bow tie look even more ridiculous. He takes a quick drink, then sets the still-steaming mug of tea on a lip near the top of the console and pops off a panel to fiddle with the wiring inside.

John makes himself comfortable on one of the little black seats set into the railing. "Yes, well, I've had quite a lot of practice dealing with impossible things. And impossible people."

The Doctor looks up from the console, though not at John. "Have you now?"

"Yeah. I had – this friend. My best friend. You remind me of him, just a little." John allows himself a smile, just a small one. Sherlock would never believe any of this. "You're both mad, that's for sure."

The Doctor appears to have gone back to his work, but he asks, quietly, "What happened?"

This isn't a conversation John's had with anyone except his therapist. Mrs. Hudson knows what happened, and Molly knows, and Lestrade knows. Even Sarah and everyone at the clinic knows. Harry knows, and even if she didn't, they wouldn't talk about it. His heart feels like a stone in his chest, and his throat feels twisted and choked, like there are hands locked around it.

"He died." John forces the words out, pulls the hands off from around his throat. "Just over a month ago. Killed himself."

The Doctor isn't even pretending to work now. He's staring right at John, and even though his face is young, John thinks that in this moment he looks impossibly old, and impossibly sad. Even though John is the one whose hands are shaking, all of a sudden he feels as though he ought to be doing the comforting.

He thinks about it for a minute, turns the idea over and over in his mind, before he decides to hell with it and asks "And you? Who'd you lose?"

The Doctor looks a little shocked, and John feels a swell of ridiculous pride, can't help the wouldn't you be proud of me, Sherlock that runs through his head. Not that it matters too much, because the Doctor glosses right over John's question as though he'd never asked it – packs away the sadness in his eyes and composes himself admirably. Instead of giving an answer, he asks John another question.

"Your friend. What was his name?"

John's very proud of himself when he gets out "Sherlock. Sherlock Holmes." without so much as a hitch in his voice.

The Doctor straightens so quickly and so dramatically John's surprised he doesn't hear the man's spine crack. The sad old man is utterly gone now, replaced again by delighted child as the Doctor shakes his head and says no in a tone of voice that absolutely means yes. "Sherlock Holmes. Your best friend's name was Sherlock Holmes. And you're Dr. John Watson?"

"Er–" John pauses, partly due to confusion and partly because the enraptured look on the Doctor's face is pretty damn unnerving. "Yes. Is that important?"

"Important? It's fascinating."

"What is?"

"You. This. Cyclical narrative multiplicity." The Doctor pronounces this with gravitas, as though it's a phrase John should recognize. He thinks it sounds like rubbish.

"What the hell is that?"

"No idea. Just made it up." The Doctor gestures enthusiastically with both index fingers, and John is powerfully reminded of a professor he'd had at uni who got very excited about the Napoleonic Wars, and used to gesticulate wildly whenever he lectured about them. "But what it means is that stories - the big stories, the important ones - have a way of cropping up again and again, all over the place. It's the reason you get fifty different versions of Cinderella on the same planet alone, plus another couple hundred out across the universe. Different cultures, different continents, different galaxies, but the same story - bright girl, rubbish family, some sort of dance or test or contest. Fancy dress usually gets involved at some point."

"And...what's that got to do with me?"

The Doctor turns his gaze towards John, and he feels as though he'd suddenly been put under an extraordinarily powerful microscope. It's the same way he feels - used to feel, God - whenever Sherlock devoted a particular level of attention to him. It's uncomfortable and intoxicating all at once, the feeling that there's nothing he can hide, nothing that's safe, not from him. "You're not a story. You're a person. At least I think you're a person. Are you a person?" He pokes John in the chest, hard enough to make him flinch, then rummages around in his jacket, abandoned on the console, for the little metal device from earlier.

John suffers through a few seconds of the device being waved in his general direction, humming and glowing, before he bats it away. The Doctor makes a noise of petulant irritation. "Yes, of course I'm a person." John snaps. "What are you on about?"

The Doctor pulls his hands back towards his chest, fingers curling into fists as though he can pull the words back out of the air. "Absolutely nothing. Forget I said anything."

Then the TARDIS lurches and groans, and John finds himself thrown out of the little jump seat as the Doctor shouts excitedly, dancing round the console and pulling levers, pressing buttons.

He knocks his head against the railing and stubs his toe against the console, but mostly John just wants to laugh, because this is mad and he probably is too – he's probably gone off the deep end, and this is all just something he's dreamed up while he dribbles on himself in a mental ward someplace.

But he feels like laughing, really laughing, stealing-ashtrays-from-Buckingham-Palace laughing, for the first time in what feels like years – and so he does, and the Doctor laughs with him.

Once the TARDIS has settled, the Doctor snatches his coat up from where he'd draped it over the console and makes towards the door. "Where have you taken us, old girl?"

John follows him, not sure what else there is to do at this point. He half expects that when he steps out the door they'll be on the moon. The other half of him expects to step back out onto the dreary street around the corner from Harry's flat.

He certainly doesn't expect St. James' Park in midmorning. From his rather crestfallen expression, the Doctor didn't either.

"St. James' Park? Why on earth are we in St. James' Park?" The Doctor tugs his coat back on. "Give me a mo', John, going to check the date. Maybe we've got an interesting year, at least." The Doctor ambles over towards a group of people huddled around a coffee cart, presumably to ask after the year.

John realizes, suddenly and to his great discomfort, that he's standing in wet grass wearing only his socks. There's mud squelching between his toes, and he's got to look absolutely ridiculous standing there in his stocking feet and brown jumper, like a sleepwalker wandering far from home. He's weighing the pros and cons of just taking his socks off and risking a quick rinse-off in the lake when he looks up and over towards the walking path.

There's a familiar coat and a familiar head of curly dark hair sitting on one of the benches. The man – very tall, even sitting slightly slouched – can't be anyone else, just can't be, because John knows that head and that coat and that scarf and that ridiculous sprawling way that his best friend sits.

It's Sherlock. Suddenly, knowing the year is absolutely vital. Something icy-hot, halfway between terror and excitement, explodes in the pit of his stomach.

"John?" The Doctor's voice snaps him out of his reverie.

John whips round, more out of habit than anything else. The Doctor is clutching a newspaper and eyeing him questioningly. "See something interesting?" the other man asks, a bit of poorly concealed hope in his voice.

He looks back over to the bench, about to respond in the affirmative, but it's empty now. Instead, he makes himself look back at the Doctor and shake his head no.

"Right, then. Back to the TARDIS."

"We're not staying?"

The Doctor sniffs indignantly. "Don't be ridiculous. It's only 2017, hardly a banner year, and it's a Sunday. I never land on Sundays." He ducks back inside the TARDIS, still muttering – to the machine itself, apparently – that Sundays are rubbish, and how…she? ought to know better.

John follows him inside, but he pauses in the doorway, one blue door half shut as he looks back at the bench one more time. It's still empty, and for a moment he's convinced himself that it was just a mirage, a figment of his grieving imagination, born from the same place that choked out do me a favor and just stop this in front of Sherlock's grave.

Then he goes to close the door, and just before it clicks shut, just before the Doctor throws a lever and sets the column off whooshing and humming again, he sees a flash of black coat and dark hair and pale eyes, far across the park–

–and he knows.

John is back in the jump seat, watching the Doctor fiddle with one of the monitors on the console – apparently trying to ascertain whether or not the Ffer– whatever they're called, the bug-people – have been well and truly shaken off their tail. It only takes a few seconds of toying with the monitors and assorted bits and bobs on the console before he crows "Success!" and looks expectantly at John, as if waiting for praise.

"So…you can take me home now, then?" John asks, shifting on the rather uncomfortable little seat.

The Doctor purses his lips and pauses for a minute, as if weighing two options in his mind. "I could." Then he looks right at John, and the microscope feeling is back. "Or you could stay, if you like."

John thinks about it, for a minute. He looks around at the white-and-blue glow of the TARDIS' lights, and the shining metal that lines the walls. He looks at the glowing column in the center of the console, still making that oddly calming humming noise. He looks up and through the microscope that is the Doctor's gaze and sees stars and supernovas, past and future, time and space.

He thinks about the back of that familiar head, about that long black coat spread across the bench in St. James' Park. He thinks 2017, thinks about terrible wallpaper and heads in the fridge, about Tchaikovsky at three in the morning and texts signed SH and bullet holes in the wall. He says, "That's all right."

For once the Doctor's face is quite unreadable, but there's curiosity in his voice when he asks "Why?"

John says, "I'm waiting for someone."

"I'm looking for someone." the Doctor counters.

"Right. Clara." John screws up his face in confusion. "That's right. Why are you looking for Clara?"

"It's…quite a long and confusing story. Your ex-sister-in-law is – well, let's just say she's a curiosity." The Doctor fixes John with another assessing look. "A curiosity surrounded by curiosities, apparently."

"Yeah, and what's that supposed to mean?"

Again, the Doctor skips right over John's question, asking one of his own instead. "You never did tell me what year it was, back at your sister's flat. When shall I be dropping you off?"

"2012."

"2012!" The Doctor slaps a palm to his forehead. "No wonder she wasn't there. Overshot by at least two years, I did." He rubs his hand back and forth, scratching idly at his hairline. "Ah well. Have to try that again."

The Doctor shakes John's hand and tells him thank you – warmly, sincerely, like this mad little interlude has been a genuine pleasure. He shakes his head as John responds with you're welcome and then says, a little disbelievingly, "John Watson and Sherlock Holmes. Imagine that."

It isn't until the TARDIS has dematerialised with a groan that John realizes the Doctor's dropped him off four blocks from Harry's flat, and he's still got nothing on his feet but wet, muddy socks.

Five years later, John and Sherlock go to St. James' Park on a Sunday morning, and at first he doesn't think anything of it.

He's under a tree, looking at the ducks milling about by the water and listening to the sound of Sherlock rustling around in the branches above him. It's all something to do with parsing the distance between a particular branch and the ground, and determining what sort of impact pattern might be created in the grass - mostly by tossing down, with varying levels of force, whatever moderately heavy objects he'd managed to stuff in his coat pockets. So far, John has spotted three apples, a biscuit tin, and the headphones that are usually tucked on the wall-mounted moose's head.

Personally, John's just glad Sherlock hasn't started throwing himself from the branches yet. He really doesn't want to have to add an A&E trip to this day.

He's still looking at the ducks when his eyes drift across the lake and he sees it - the blue box, tucked in between two trees, the same place he remembers it being all those years ago. He knows that if he looks for him, he can probably locate the Doctor, somewhere in the small crowd of people by the coffee cart, nicking a newspaper.

John knows, that if he were to move to the left, just a little, he could catch a glimpse of himself on the other side of the box, worrying over his wet socks. Somehow, he thinks that's probably not a good idea.

But he knows what is a good idea. He knows, now, what needs to happen.

He squints up into the tree, looking for his friend. "Sherlock, I need you to do me a favor-" Sherlock doesn't appear, but John hears him make the beginning of a cross I'm working noise. He cuts him off. "-and you can't ask me why."

Sherlock pokes his head out of the tangle of branches, an expression of genuine interest on his face as he cautiously asks, "Why?"

John shoots him a dark look. "I just told you not to ask me why."

Sherlock huffs indignantly, and briefly disappears back into the mass of leaves before dropping - entirely too gracefully, for a man nearly forty - to the grass at the base of the tree. He takes a moment to brush the assorted detritus from his coat before turning back to John "What, pray tell, is this inanity that you want me to perform?"

"I need you to sit on that bench there." John points to the bench on the walking path opposite, the one he knows the earlier him can see from the TARDIS doorway.

"You want me to…sit on a bench? And do what?" Sherlock's tone is equal parts curiosity and exasperation. Time has done little for his dislike of being left out of the loop.

"Nothing. Don't do anything. Just…sit there, for a minute or two."

Sherlock's annoyance at the lack of explanation is clearly getting the better of him – he's screwing up his face the way he does before exploding into a storm of frustrated babbling. "John–"

"Sherlock." He cuts him off again, puts just enough steel in his voice to make Sherlock's eyes, pale and brilliant and wondering, snap to his. "Just this once, I need you to do this and not ask. It's important."

It's been five years, and for three of them John was alone. They don't talk about what that means very often. Mostly they try to act like nothing has changed, like those years Sherlock was gone were a blip, an anomaly that won't be repeated and therefore needs no discussion. But every once in a while, John brings those empty years to bear – lets the weight of all that waiting show in his face and come out in his voice.

When John does that Sherlock doesn't argue, doesn't scoff. He just listens – like he's listening now, as he walks across the grass and over to the bench, as he sprawls across it and takes up the posture that's been burned into John's memory for years – and it's heart-wrenching and heart-warming all at the same time, this odd and patched-up thing they have between them, this thing John wouldn't trade for all of time and space.