Warnings for: Alcohol, swearing, violence, sex, adult themes

Sweat trickles down John's neck, pooling beneath his hairline and collecting in the collar of his shirt. The sun is blinding, but he doesn't shield his eyes as he looks skyward - can't move his arms, with the way he's got one frozen and clutching his phone to his ear, and the other clenching and trembling at his side.

Up on the roof of St. Bart's is Sherlock - funny, John thinks, because this is where they met, and now they've come full circle.

"He won't get away with this. Sherlock, Mycroft is on your side, Molly is on your side, Mrs. Hudson is on your side, I'm on your side-"

"I lied about the whole thing, John! I made up Moriarty, I hired Richard Brook. It was all an act." Sherlock takes a deep breath, but John won't let him finish.

"Damn it, Sherlock! Don't let this get to you! We can get through this, you and I."

How John wishes Sherlock would scoff at this last remark, at the idea that another person could influence his own self-confidence, at the idea that John could possibly help him with something personal. All those moments that John flinched when Sherlock dismissed his attempts at connection; what he wouldn't give now for one more eye-roll, one more toss of his perpetually disheveled hair.

But there is no reply.

"Come down," John says into the phone.

"No," Sherlock replies, his voice odd and tinny through the cheap speakers.

"Get down," John says, but it's a sorry attempt at authority. Sherlock was never one to obey orders to begin with.

"Please," John tries again, and there's a flare of static on the other end. Is Sherlock... crying?

"You're being an idiot!" John shouts. "Who cares about what they're saying? You're real. I know you are. You're real to me."

And shouldn't that be enough?

But he can see Sherlock shaking his head, notices with a punch of fear to the gut that his best friend in the universe is toeing ever closer to the edge of the roof.

"Don't," John says warningly. "I swear to god, Sherlock, don't-"

"I'm sorry," Sherlock's saying. "John, I'm sorry-"

Sherlock jerks the phone away from his ear and lets it plummet one, two, three- eight stories towards the pavement. His arms stretch outward and for a moment the clouds part and the sun flares behind him; he is a veritable guardian angel on the roof of St. Bart's and John can't tear his eyes away.

"Sherlock," John calls hoarsely, but his words fall on deaf ears. Sherlock's phone is shattered on the cement, but John can't seem to let go of his own. "Sherlock!" he yells. "Don't! Whatever you're doing, just don't-"

Up on the rooftop, Sherlock is shaking his head. He's made his decision.

And Sherlock Holmes jumps, his coat flailing in the wind, limbs outstretched, and John's phone finally slips from his fingers, and Sherlock is inches from the ground-

A strangled scream rips from John's throat. He knows he's too late but he runs to Sherlock anyway, feet pounding across molten pavement, arms out as if he dared catch him-

Suddenly, electricity skitters along his fingertips, crackles across his bones and lodges beneath his skin. It's high noon and every breath he takes is a laborious one. He feels as if his body is being torn in two, every ligament stretched at the seams and all of his cells being forced to dissect at once.

Trauma-induced shock, the doctor in the back of his head notes, and when he goes blind it convinces him that it's just another part of the process.

"Sherlock- Sherlock-"

John collides into something sharp and heavy, and around him there is the sound of glass shattering. He realizes he's on the floor- not concrete, too smooth and cold for that- and someone's screaming at him.

They've got a Scottish accent, whoever it is. Can't really tell, with the sun flaring so violently, and everything coated with static. John feels nauseous. His whole body aches, his muscles feel strained, and exhaustion consumes him, reducing him to lying prostrate on the floor.

The Scot's still yelling, and John finally pieces together the words.

"What the hell? Who the hell are you?"

"But... I... Sherlock..." John mumbles to himself. His chest constricts painfully, and breathing feels like forcing air through a bellows.

"Shlock?! Shlock the wot?" A balding man with a round face bursts from the bright lights- not the sun, John notices, but harsh fluorescent bulbs. John finally focuses his eyes and is met with the barrel of a gun. His hands instinctively shoot into the air; if nothing else, John has been trained for situations like this.

"I- where am I?"

" 'Where are ye-?' Who the fuck are you?"

"Dr. John Watson, former Captain of the Fifth Northumberland Fusiliers," he says breathlessly. Some bits of information are just ingrained.

"'Captain'?" the balding Scotsman repeats. "By whose authority have you boarded this ship?"

"SCOTTY!"

An American accent this time. The lights still in his eyes, John shuffles awkwardly on the floor, trying to haul himself to his feet. Scattered around him are sharp metal instruments he cannot name, and to his left lies an upended red toolbox. John's ribs ache and he can already imagine the bruises; he must have run right into it.

"Jesus, Scotty, where'd you pick this one up?"

John flinches as a harassed-looking man in a blue shirt bustles in past the one called Scotty to push him firmly into a chair, shine a flashlight in his eyes, and shove a little machine up his shirt.

"I didn't do it on purpose!" Scotty protests, glancing over at John apprehensively. "'E just swooped in!"

"Excuse me-" John begins.

"He could have flamonidas dysentery, do you know that?" the angry one in blue growls. He squints at the results on his machine, then pulls out what John supposes is some kind of stethoscope, only to proceed to stuff it into his nose. "Or Sicorzhan gangrene!"

"Could you please not-" John tries again.

"-I once heard about a whole ship that came down with it and by the time anyone could warp towards a hospital half the crew's dicks were already rotting off-"

"Get off m-"

"Out of the way!"

The one prodding at John with what he now figures are medical devices sends a death glare over his shoulder.

"Jim, stay back, I still haven't cleared him for Gamma Ten tonsillitis-"

"Knock it off, Bones," the man called Jim orders.

To John's surprise, Bones sighs and obeys.

"Scotty," Jim says, "Care to explain yourself?"

"Captain- I-" Scotty stammers.

Jim's attention snaps to John. "Who the hell are you, and why are you on my ship?"

"That's what I was tellin' 'im! You don't just board the USS Enterprise without some kind of clearance!" Scotty interjects defensively.

John looks between them in confusion. "Ship? Is this a submarine?" Has to be, right? With those clinically white, sloped walls, glass doors, and odd little panels?

Bones snorts and Jim gives John the strangest of looks, as if he isn't sure whether to yell or simply ask if this is all a big joke.

"Wrong end of the universe, mate," Scotty pipes up.

"I think my great-grandfather once rode in a submarine," Bones adds. "Hold on, Jim, I'm going to check him for-"

"No," John says firmly, knocking Bones' hands away. "No more of that! I'm not diseased!"

"Oh? Where are you from?" Bones demands. "I'll have you know that over 75% of the population of this quadrant has had Maeglian fleas-"

"I believe fleas will be the least of our worries if we are this susceptible to strangers warping aboard our vessel, Doctor."

John starts in his chair at the sight of dark hair and a slender figure whose movements speak of calculated grace, whose eyes hold the keenest sense of control and understanding-

"Spock! There you are!" Jim says, and that breaks the spell.

This man with the rigid haircut and the strange, pointy ears is Spock, not...

"Sherlock," John gasps to himself.

"What?" Jim says.

"Sherlock!" And then John remembers everything. Escaping from being arrested by Lestrade, dashing handcuffed together through London at night, seeing Sherlock on the roof of the hospital and watching him dive-

"He's hyperventilating," someone's saying, as the room slides out of focus and begins to darken.

Jim is shouting orders, and John is dimly aware of losing his balance and sagging off his chair. Jim ducks under his arm, lifting him before he can slump to the floor, and in the back of his head he muses that Jim is strangely young and handsome to be a captain.

They're waiting for John when he wakes.

"-dressed in civies," Jim is saying to Spock. "But Scotty said he's a captain."

"Are you suggesting espionage?" Spock replies calmly.

"He's not recorded anywhere in Starfleet's database. Sulu checked twice."

"Suspicious indeed."

"Ah! You're up!" Jim exclaims when John stirs. "Watson, is it?"

"Doctor Watson," John replies snippily. He slides off the bare cot they'd thrown him on, shaking out his stiff limbs. "And who are you?"

Jim chuckles, but Spock stares John down, expression tightly controlled, with his arms behind his back.

"Now, Doctor, would you kindly explain to us how the fuck you got onto my ship?"

"Ship? Where are you sailing?" John asks.

Jim glances at Spock uncertainly.

"What?" John says. "What's wrong?"

"I believe the Captain is simply amused with your use of rather... archaic vocabulary," Spock replies.

"Sailing!" Jim says. "That's funny, though. Haven't really thought about it that way."

"I don't understand," John says.

"We are flying, Doctor," Spock says. " 'Sailing' implies that we are travelling through a body of water rather than a vacuum."

"A vac-" To John's left is a window, and beyond it is nothing but black.

They're joking, aren't they? This is all a sick prank-

"Catch him, Spock!"

"-no, no, I'm fine," John insists, shooing him away. He's feeling rather lightheaded, a little sickly, but he isn't keen on falling unconscious yet again in a room full of strangers. "It's just- you said- Starfleet, right? Starfleet?"

Outside the window, embedded among the black, are pinpricks of light he didn't notice before.

"Space," John says, putting two and two together. "We're in space."

"...you're not from around here, are you?" Jim ventures.

"I am now inclined to return to my first hypothesis: he is not a captain as he claims. Perhaps he is lying about his name as well," Spock says.

"I'm not lying!" John exclaims. "I'm John Watson of the Fifth Northumberland Fusiliers-"

"A convincing story, Doctor, but we are not fools. The Fusiliers have been disbanded for nearly 200 years."

Behind Spock's tightly controlled expression is an infuriating smugness that makes John want to rip off the tips of his pointy ears.

"I- I-"

"John Watson, if that is indeed your name, how did you manage to warp onto our vessel?" Spock says.

"I don't know!" John says. "One minute I was in London, waiting outside St. Bart's for my friend-"

Sherlock.

"Oh no," John says. He remembers now. Sherlock on the roof- "Oh no. No, no no-"

"London?" Jim demands sharply, "What the hell were you doing there?"

"Captain, he appears to be going into shock."

"I can see that, Spock," Jim replies exasperatedly. "Doctor Watson, you alright? Do you want me to grab my CMO?"

"No- don't need- Sherlock, get Sherlock- before he-"

"Scotty informed me that he mentioned the name several times after warping," Spock says.

"Who's Sherlock?" Jim asks. "John, breathe. I need you to stay with me. Breathe."

"Tr-trying, he just-"

"John, who's Sherlock?" Jim asks firmly.

Spock's watching John without a trace of emotion, and John thinks about how much he resembles Sherlock right now, when the consulting detective was more machine than man-

"-you look like him," John says. He accepts Jim's hand on his shoulder, letting it ground him. "It's odd. You look just like him."

"Like who?"

"Not you," John replies. "Spock. He looks like Spock."

"Well, I assure you that our Spock's one of a kind." Jim's talking to John slowly, patiently, like he's a child. He tries not to resent it.

"No." John shakes his head. "It's the way he holds himself. It's the look on his face that's constantly showing off that he knows something you don't. That bastard. Stupid, stubborn bastard."

"Looks like he's got you down, doesn't he?" Jim grins at Spock.

"Me... or perhaps someone else aboard this ship."

For the first time, John sees a glimmer of curiosity in Spock's eyes.

"What exactly does your friend look like?" Spock asks.

John glances at Jim, who nods in encouragement.

"Dark hair," John says, throat dry. "Tall and scarecrow-thin. Cheekbones you could cut yourself on. And... clever. Always clever."

Spock's lips purse into a tight line. "Captain."

Jim glances back, and silent agreement passes between them. He nods.

"Doctor Watson," Spock says, "you are under arrest."

"What?!" John steps back, aghast. "Why-"

"We have reason to believe that you are connected to a high profile intergalactic criminal accused of the conspiracy and execution of terrorist attacks on London."

"You've got to be kidding-" John starts furiously.

"Watch it, Doc," Jim says. His jaw is set, and he reaches for his gun.

"London? I was just there!" John exclaims. "What happened?"

"People died, Doctor," Spock says simply.

Jim points his gun right between John's eyes, and Spock signals to someone behind them. A security guard steps into the room, handcuffs clinking at his waist.

"I don't know anything about that!" John protests. He looks pleadingly at Jim, and the captain seems to hesitate, glancing at Spock for affirmation. Spock, however, does not break his steely gaze.

Resignedly, John accepts the handcuffs the guard slaps around his wrists and follows him out of the room. His mind races; what the hell happened in London?

There's a distracting little twittering ahead. It's the guard, singing under his breath. But it's a tune John knows, a song he's certainly heard before...

"Whether you're a brother or whether you're a mother-"

"Is that 'Stayin' Alive'?" John asks incredulously.

"You recognize it?" A familiar drawling voice responds. "Funny, no one else here does."

John's blood runs cold. It can't be. It's not possible.

"You're-"

"Richard Brook." The guard finishes the thought for him, turning around with a lazy grin. "Also known as Jim Moriarty."

John stops in his tracks, acutely aware that he possesses neither a weapon nor even a free hand. How the hell could this be happening? Apparently he's been beamed onto a bloody spaceship; how could Moriarty be there too?

"Oh, come on," Moriarty coos. "Don't want to raise their suspicion, do you?"

John swings his bound fists. They connect with the side of Moriarty's head, but the criminal recovers immediately and sends a punch into John's gut. John doubles over, but Moriarty hauls him roughly to his feet. He tries again, and Moriarty swats him away like a fly.

"You're a liar and a criminal and a murderer-" John starts angrily.

"Accused liar, criminal and murderer," he corrects. "All charges were dropped, remember?"

"Once they find out-"

"Oh, will you tell them?" Moriarty laughs. "The 300-year-old 'Captain' who beamed onto their ship without permission? The batshit-crazy Methuselah currently being escorted to a holding cell?"

"Well, what about you?" Not the greatest comeback, but his unadulterated hatred for the man has made him tongue-tied.

"Oh, John," Moriarty says smugly, "I've been a guard on this ship for five years. I've been with them through thick and thin, I've comforted them when they cried... Hell, I've watched them get so shit-faced they couldn't see, heard them spill their their deepest, darkest secrets, and brought them ginger ale in the morning. Like they'll believe the five-minute man over their beloved Yeoman Brook. Now for God's sake, follow me unless you want more trouble."

John, still stuttering with ire, yields and trails after Moriarty through the winding white-paneled halls of the ship. His heart's now racing in addition to his mind.

"What the hell are you doing here?" John manages through gritted teeth.

"Oh, it's no coincidence." Moriarty walks tall and confidently ahead of John, his slimy voice emanating from a certainly smug expression. John wishes he could see Moriarty's face. Wishes he could punch it, or better yet, take a crowbar and- "Let's just say that you ought to be thanking me for this opportunity. Not many can say they've experienced the luxury of time travel."

"Time travel?!"

"Well, obviously. Johnny boy, open your fucking eyes and look around. Has Sherlock taught you nothing?"

John begins to feel the gravity of the situation: the sudden move from the street to space, the confusion of the crewmembers, the attacks on London...

John's stunned into silence. "...How?" he asks finally.

"It's really not that difficult once you 'familiarize yourself with the technology'," Moriarty says, "I mean, if the bastard in the control room can do it-"

"What year is it?"

"2273 AD. Exactly 261 years from where I left you. And you're awfully lucky, the first experiments with time travel blew up dozens of people."

John rolls his eyes. "Lucky. Yeah, I'd say my current situation shows nothing but a bright future-"

"I also doubt that many can say they're witnessed a friend return from the dead," Moriarty continues, "or at least partially return-"

"What the hell have you done with Sherlock?"

"All in time, impatient one. Here, we've reached home, sweet home." He presses a button next to a tinted glass door, which slides open, revealing a small room. "In you go."

John enters reluctantly. "You won't get away with whatever it is you've done. Not this time."

Moriarty sneers and presses the button again, closing the door. A small opening is revealed in its center. "Handcuffs, please."

John sticks his hands out, anxious to prove his courage and confidence in Sherlock; but he wonders to himself if there's even a Sherlock left to defend.

Moriarty removes the handcuffs from John's wrists, massaging his palms with an aggressive mock-sensuality. John yanks his hands back in disgust, which only causes Moriarty's manic smile to turn into peals of laughter.

"You think you're so brave," he whispers with glee. "So loyal, I admit it's really rather touching. But my dear Doctor Watson, may I remind you that you're alone in a jail cell 300 years in the future with no friends to come to your aid? And what's worse..." He trails off.

John begrudgingly takes the bait. "What?"

"I have access to Sherlock. Or what's left of him, rather. I'd advise you not to make me too angry. You see, I put a lot of effort into this part of the game, and I'd hate to end it early and start from scratch. Sherlock was always my favorite opponent... but you are most definitely rising up the list."

Moriarty backs away from the door slowly, seeming to disappear into the darkness cast by the glass' tint. "Your move, John."

And he's gone.

John sits on his bunk in his clinically white cell, his breath stuttering, desperately willing himself not to pass out again.

Beneath the soles of his shoes, the Enterprise is humming.

The Enterprise. The spaceship called the Enterprise-

"Oh God," John wails. "Oh God."

He paces back and forth. He's got to get out. One way or another, he's getting off this ship. The next time they dock- is that what spaceships do?- he'll connive his way out. Break a few wrists, if he has to, steal someone's gun...

There's a single window in his cell, the diameter about the width of his shoulders. He grips the rim and presses his face against the glass.

Nothing.

Outside is an emptiness that stretches on into eternity. He's gazing at the universe in its purest, most unadulterated form. They are travelling through the remnants of worlds, reduced to ash millenias in the past, and through the breeding grounds for galaxies that will emerge long after they are gone. Most frightening of all, they are travelling through nothing, and he is centuries ahead of his time, and everyone he knows and loves is dead-

Mind reeling, he clamps a hand over his mouth, fighting the urge to vomit. He counts sets of 4, then 8, then 4 again when he trusts himself to lower his hand. The glass is cold against his forehead, and if he stands motionless he can feel the ship vibrating ever so quietly.

...it's all so preposterous, really, if he thinks about it.

It's a flat fact: time travel's impossible. If the technology existed in any form, Sherlock would have mentioned it. Would have pursued it on his own, probably, out of some kind of arrogant belief that he could alter the past and thus improve their present and future. Sounds just like the sort of thing he'd do.

The idea of a spaceship's partially credible, but John still hasn't seen the ship itself yet, just a few lab-bright hallways and fancy glass doors. Spock's ears were a curiosity, but there's a thing called prosthetics.

Then there was Moriarty.

What if the entire thing's just a ruse? Another of those infuriating games the consulting criminal's so damn fond of?

"Drive me into insanity, will he?" John mutters to himself. As if ruining Sherlock's career wasn't enough. As if compelling him to take his own life wasn't-

John doesn't know how, but he stumbles onto the cot before he can collapse.

Damn that Kirk, with his good-cop attitude, and that Spock with his stupid, pointy (and surely artificial) ears. They're just paid, highly-trained actors. Richard Brook's, the lot of them.

Time travel? He lets out a harsh bark of laughter for allowing himself to believe for even a moment that such a thing could ever be true. Moriarty's probably got him locked up in a tin can in a dark warehouse. Maybe, once he gets bored of the "Starfleet" charade, he'll strap some bombs on him, only this time John will be ready, and he'll drag the bastard to hell with him-

"Excuse me!"

John jumps and curses.

There's a young man in a gold shirt, gold like Kirk's, crouching by his door.

John eyes him warily. "What do you want?"

"Well, sir," the man continues, with the heaviest Russian accent John has ever heard, "I just wanted to see how you were doing!"

...he's joking, right?

"How much is he paying you?" John demands.

"What?"

"How much is Moriarty paying you?" John roars, but if the name means anything to him, he doesn't show it.

The young man looks around worriedly. "Quiet, please! I don't want anyone to know I'm here."

"Why's that?" John growls, crossing his arms.

He looks flustered at this. "Technically, you are our prisoner, and as an Ensign I really should not be-"

"-let me out," John snaps, not caring, and certainly not looking to be buttered up by a pretty face, no doubt planted by Moriarty. "Now!"

"Please-"

With a shout, John slams against the door. It's made of glass, or so he thinks, and it ought to shatter- but instead, he's punished with a shoulder full of bruises and a ringing in his ears.

"Unbreakable," the young man says. "To you, at least."

"What the fuck do you want?" John asks again, ears hot with embarrassment.

"My name is Pavel Chekov," the ensign replies brightly, "and I wanted to ask you how exactly you warped onto our ship!"

"How many times do I have to tell you bastards that I don't know?" He could strangle the kid right now, break his lying bones and dump the body at Spock's feet.

"Please do not take it the wrong way, sir-"

"Doctor," John interjects.

"Doctor," Chekov repeats eagerly, "but I was wery impressed!"

"...what?"

With a grin, Chekov sidles as close as he can against the door, all smiles, as if John's a celebrity. "There is only one person with the formula to achieve such a thing. And that is Scotty!"

He must mean the red shirt who pointed the gun before he'd even found his bearings.

"Where did you study?" Chekov asks before he can take his next breath. "MIT? New Delhi? Aberdeen?"

"I-"

"It is quite an anomaly to meet another expert in warp technology, let alone one who is also a man of medicine!"

When John merely stares at Chekov, the kid's smile falters, and for a second he almost feels guilty.

"Have I upset you, sir?" Chekov asks.

"Upset? You're asking if I'm upset?" John growls darkly. "Today I got interrogated by an overgrown elf, handcuffed and thrown into an oversized closet, and I just found out that the maniac who practically murdered my best friend is trying to play one last mind game by convincing me that I'm on a spaceship. In the future."

"But you are," Chekov replies.

"Fuck off."

"But you are!"

"What did Moriarty promise you?" John asks coldly. "Money? Power? Women?"

"Moriarty?" Chekov wrinkles his nose in confusion. "Who is Moriarty?"

"You listen here, you son of a bitch," John says, balling his hands into fists as if he dares strike Chekov down through the glass. "I don't know shit about 'warping' and even if I did I wouldn't tell you how I did it. So you're going to let me out right now so I can strangle that fucking l-" But now the poor kid's looking at him as if he just told him that there's no such thing as Santa Claus, and that little light of excitement is gone, replaced by growing hesitation. "...you have no idea what I'm talking about, do you?" John tries again, softer this time.

Chekov shakes his head.

"Oh God." John slides to the floor and rubs at his eyes tiredly.

"...I understand that being arrested can be a stressful experience," Chekov says timidly, settling cross-legged on the floor to meet John's eye-level. "Are you hungry? I have gotten quite good at replicating stew."

It almost pisses John off, the way he can't quite figure Chekov out. Chekov's smiling again- trying to, at least, no thanks to John scaring the shit out of him- and he's fiddling with the embroidery on his sleeves.

Harmless.

The kid is harmless.

John can feel it in his gut.

Feeling embarrassed, he clears his throat. "How old are you?" he asks.

"Nineteen, sir."

"That's, ah, that's quite young to be an officer, isn't it?"

"Wery." He grins toothily.

"Can I ask you some things, Chekov?" Because as genuinely clueless as Chekov may seem, it doesn't rule out that being on a spaceship is almost as believable as Sherlock surviving jumping off a-

Ah. Best not to think about that.

"Of course," the ensign replies eagerly, and John can practically see his ears perking up.

"...I'm not from here," John says with some difficulty. He focuses on exhaling.

Chekov nods, wide-eyed.

"The ears," John blurts out, although he's got a hundred-and-one questions buzzing about in his head. "Spock's ears. They're fake, right? Plastic? Or was he deformed at birth?"

"Fake?" Chekov laughs. "They're not fake. He's a Wulcan!"

"Wulcan?"

"Oh, um..." Chekov scrunches his nose in concentration. "Vulcan," he manages over his accent.

"So... an alien."

"That is one way of looking at it. Although, as you noticed, they are quite humanoid."

"And are all Vulcans that much of a stick in the mud?"

Chekov giggles at that, and the sound puts John more at ease. "Yes. Unfortunately. They do not believe in expressing emotions. They have them, although they like to deny it."

"Spock must be a real gem, then."

"You do not like him."

"Reminds me of-" Ah. Nope. Best not to go there. "You wouldn't lie to me, would you?"

"Of course not!"

John believes him.

"So... What Spock said about people dying in London. Is that true?"

Chekov's eager face falls. "Yes, Doctor. A man blew up an important intelligence agency, and attacked Starfleet's headquarters. It was horrible." The simplicity of Chekov's statement unnerves John; this soldier - no, he's too young for that title - this boy can barely comprehend the attack. John's heard such terse comments in PTSD wards, from Afghanistan vets; such an attack would explain why they've been treating him so coldly on the Enterprise.

"Oh," he responds, unsure of what to say. "Why did he do that?"

"He is mad."

John looks down at his feet, the scuffed shoes so often pitied by Mrs. Hudson. A feeling of homesickness overwhelms him - he'd give anything to be back in his flat, sipping tea and listening to Mrs. Hudson and Sherlock bickering about the housekeeping.

"That doesn't make sense," he says shaking his head. "I was just there. I would have heard-"

"Docter, I apologize, but for mastering warp technology in such an advanced manner, you seem to be having a hard time understanding what is going on in the world," Chekov says, "This is the USS Enterprise, year 2273. I doubt you are from this place and time, yes?"

"Yes, but..."

"Time travel is not impossible, Doctor. Improbable, but it has happened before."

John nods.

Chekov turns suddenly, looking down the corridor outside John's cell.

"What is it?"

"Guards. I must not be here. Goodbye, Doctor Watson!" Chekov waves and scurries off.

John presses his face against the glass to watch Chekov disappear around a corner. His head snaps towards the sound of footsteps.

Four guards bearing large guns lead a prisoner, his hands cuffed and his eyes glaring, and four others bring up the rear. Who they're guarding- No, it couldn't be-

"Sherlock," John breathes to himself.

But in the split second that Sherlock marches past his door, John can see that only his body is present; the gait, posture and defiant expression belong to someone else.

"Sherlock!" John shouts, pounding on the glass, but the procession is gone as suddenly as it had arrived. The corridor is empty and silent, and he wonders if it had existed at all.

He collapses defeatedly onto his bunk. Every cell in his body aches with a pain he's never felt before. His eyes close, and there he is again, on the sidewalk in front of St. Bart's. He hears Sherlock's voice crying "I'm sorry," he sees that bloody coat flailing like a cape as Sherlock falls, he feels the pounding of his own feet on pavement as he rushes across the street to the huddled mass...

Curling up with his arms wrapped tightly around his knees, John is acutely aware of how far away he is from home.