The Doctor slams the TARDIS doors shut behind him and leans back against them, hearts pounding. The clamour of a Trasothian parade in full riot cuts off, and he blinks bright after-images out of his eyes. The door trembles once or twice under the enthusiastic tentacles of the blue squid-people chasing him. It makes him grin. He runs his hands over his cropped hair and pushes off the door.

"That's sorted then. Never fails! Best run of my lives, jaywalking the first day of carnival. Though, the psychic unicycles, that's new." He makes a pleased huff and strides towards the console.

Which is squarer and blockier than it should be, the light more blue, and he doesn't remember leaving the library right next to the control room when he went out. The eternal TARDIS hum shimmers in subtle disharmony just as he comes around the central time-column and locks eyes with the man in dark curls whose hands freeze on the dials.

"You!" Dark curls springs into motion, the shock in his blue eyes fading quickly into something harder as he picks up a trans-grav spanner and points it at the Doctor. "You're not welcome here." The voice is soft and rich as the velvet coat he wears, but it carries an unfamiliar bite. Hard as he has tried to forget wearing it, the Doctor knows this face. The frock coat and the cravat are just window dressing; it's the eyes that give him away, young and unburdened in a way the Doctor can never be again. But his lips thin as he comes around the TARDIS console and grips the spanner like he means it. "What are you doing in my TARDIS?"

The Doctor spreads his hands wide in surrender. Why do his hearts clench at the distrust on his other self's face? He's always known this one would have no welcome for him. "Sorry," he says, stepping backward, trying for nonchalance in his shrug, "Took a wrong turn."

"You don't take wrong turns, Master," says his other self, keeping pace.

He laughs, startled. So surprised at the mistake (as the knife in his gut twists further at the thought that this Doctor can still make such mistakes, can see a Time Lord and think it anyone other than himself) that he lets himself be backed into a supporting column. "I'm not the Master," he says. The TARDIS trembles under his feet, knowing who and what he is even if her companion doesn't. "He's gone, we made sure of that."

He should be running. Every reflex he has says he should have fled the moment he realized this wasn't his own TARDIS. But the air here tastes of intentional time, bright glowing traces of the vortex spinning out in invisible lines about them, and he drinks it all in with senses starved for it. It's still him and only him, but it's a different him and oh how he's missed not being alone.

His shoulders drop. "The Master's gone, with all the rest. Me-I'm something worse."

Close up, the other Doctor makes him feel gangly, too tall. It's not as if this incarnation is unscarred, but even the focused frown on his face isn't enough to keep him from being handsome, even pretty, just one more reminder that this is the Doctor before. He tilts his head back to hold the Doctor's gaze, and chestnut curls fall down his neck, over the starched collar. Before he cut his hair, before the war consumed the last of his vanity.

He drops the spanner and pushes the Doctor backward with a palm on his chest. Even through the jumper, the touch burns. It holds him there, implacable. "Are you, now."

"You don't know-" Suddenly desperate to escape this most dangerous of his selves, he grabs the arm pinning him to the column and twists. But his fingers brush bare skin at his younger self's wrist, and it's enough to send him reeling. Touch telepath, oh yes. He gasps, slamming down doors in his mind-too little, too late. One after another he seals off whole sections of his past and this self's future, as afraid of the way this Doctor will look at him as he is of any paradox. He wrenches himself from the other's grip, stumbles blindly, trips over the dropped spanner and crashes into the console.

When he opens his eyes, the Doctor in the velvet coat still hasn't let him go. He's pressed up against him, full-length now, and he holds the Doctor by leather-clad shoulders until he stops fighting. The Doctor sprawls across the console with the levers for attitude control digging into his back and refuses to meet his eyes.

"So you're the one from afterward," the younger him says at last. The rich low voice is full of the expected sorrow but somehow almost entirely free of disgust. His hands dig into the Doctor's arms. "No, don't tell me. I've felt the echoes of whatever's coming, you know that. It's terrified me enough as it is."

The Doctor shakes his head, No, no, no, you only thought you knew, can't stop until his other self catches his face, holds him still.

He hears the vortex singing in the other man's veins, counterpoint to his own, feels the double-thump of his hearts doubled again. He sees them all again, burning, all the children of Gallifrey. Sees the face he wore and the moment-the moment The Moment the-other faces, as through wavering glass, men he hasn't been yet. An impossible rescue on the tip of his tongue, hope just out of reach, and then, then perhaps, and somewhere-all the children of Gallifrey in the sunshine-

The other Doctor drops his hand. The blue eyes cut straight through him, grounding him in this instant of time. "Is there any other way?"

"No," the Doctor says, but for once in this lifetime he's almost unsure. "Believe me, I've looked."

His other self nods. It has been easier to remember this self all young and vulnerable, when things happened to him rather than the reverse, or else those last desperate months of the Time War when there was no more choice and he made the universe twist and burn around him. But this is the one in between, no amnesia and no despondent last stand. The beautiful poet is stronger than the Doctor ever believed himself. He brushes long fingers gently down the Doctor's neck, and that faint hum of possibility starts under his skin again. A crack in time...

"It's going to kill me," says his younger self.

"More than once," the Doctor murmurs. He shivers.

"Hush," says his other self, and the Doctor doesn't expect the kiss. The taste of Time Lord is overwhelming, intoxicating. He grabs handfuls of the soft green velvet coat and pulls the other man tighter against him before he can think how many ways this is impossible. The younger Doctor has one hand pressed between his hearts again, the other pulling him down the few inches he needs. He remembers that this incarnation used to like kissing. He didn't remember that he was so good at it.

He feels time curling and twanging around them, like it's pure artron energy they're breathing between them instead of oxygen. Little things, things he spent lifetimes taking for granted with his own people, blind him with their beauty now and make his hearts clench. Cool hands slide up under his jumper and he gets one leg between the other Doctor's, grinding up before he can stop himself; the gasp it earns him is infinitely precious.

On instinct his mind reaches out to brush other timelines, Romana, Flavia, Susan, the Master, and pulls back as if stung when he finds traces of them where there should be none. It fades like crackling static when the other Doctor lets go of him to tug the leather jacket from his shoulders; he's not such a fool as to think it's more than a mirage born of an old man's grief and his younger self's innocence. Still he clings to the other Doctor, hungry for even that comfort. "Safe like a painting," he murmurs into the dark curls, not knowing why.

His younger self kisses him again, fierce, a challenge. "Whatever I have to be," he says, "Or do, I promise you-" The Doctor cuts him off with rough kisses down the side of his neck, big hand tangled in his hair, unwilling to hear him promise to change something he can't. The younger Doctor groans, wraps his leg around the Doctor's hip, and the Doctor gets his feet under him and spins them so he has the smaller Time Lord trapped between him and the TARDIS console.

The TARDIS thrum runs up his spine and sets every inch of skin alight. He gropes down the other's chest and encounters that ridiculous complicated waistcoat, its buttons smaller than he remembers and at completely the wrong angle. The other Doctor hears his grunt of frustration and flashes him a blinding smile. Nimbler fingers flick open the waistcoat and shirt, eyelashes dark against his cheeks as he looks down.

"Stupid costume," the Doctor grumbles, "Steampunk and Halloween-" His other self's hips rock down as the shirts come free, and the Doctor growls breathlessly and shoves him back across the controls, pins him flat with hands on either side of his head. He can feel him hard through the thin trousers and his own jeans.

"Jumpers and denim!" The indignant complaint is so familiar it makes his breath catch. His selves have always had a contrary streak; he's not the first to choose as much difference from his predecessor as possible.

They're pressed together perfectly now and it takes just one deliberate roll of his hips to make the blue-grey eyes go wide. Spread out like this, white shirt against bare skin, hair wild and pretty mouth open on a moan, it makes the Doctor want to bite and take and mark him, to hurt and protect in equal measure. It can't be worse than what he'll do to him simply by living.

But the other Doctor fists his hands in his rucked-up jumper and grinds against his thigh, too bright and determined for the vulnerable look of a moment ago. "Move, damn you," he pants, fucks up hard, and the Doctor feels the vortex spiralling through his mind again. He moves, bites desperate kisses into the other's lips, and the silver trees of Gallifrey, the suns bright in an orange sky, and he takes Susan's hand and he runs-

The TARDIS shivers beneath them, like a gentle caress, almost like a smile.