Archive of Our Own

Chapter Text

Summary: The grass is always greener in somebody else's universe.

The Doctor leads an unpredictable life; he'll certainly cop to that. A surprising fact, considering he's the owner of a time machine and all. One would think he'd see a few more things coming now and again.

Case in point: when Donna puttered off to bed last night he'd had absolutely no inkling that by teatime today Rose Tyler would be dumping a duffel full of her clothing onto the entry ramp of the TARDIS just before throwing her arms around him and squeezing him so hard his back cracked. "Thank god, I don't think I could've lived through another Easter," she'd mumbled gratefully into his tie as he'd stared down at the top of her blonde head, momentarily speechless. "Promise me we'll never jump into a time stream near that bloody holiday ever again."

No, he definitely hadn't been expecting that development. Nor had he been expecting the surprisingly thorough snogging that came with it.

And if he hadn't been expecting that, well, you can be certain he hadn't been expecting all the dashing-about-saving-the-universe that happened a bit before supper. Nor had he foreseen the being-split-up-into-all-his-tiny-component-molecules-by-fiendish-alien-overlord that occurred in the process of the previously mentioned heroics, nor the desperate-putting-the-Doctor-back-together undertaken by Rose, Donna, and an unfortunately overenthusiastic TARDIS.

No, he'd planned simply to have a nice, quiet day at the seashore.

Funny, how he never quite manages those.

***

The Doctor blinks, striving to focus as his body puts itself back together around him. It's an odd feeling, with stretching and pinching and twisting where there's never been any before, shooting all down through his toes and up behind his belly button. Not like regeneration: all heat and flashing pain, that. Much more like what a giant rubber-band-person might feel like if there is such a thing, folding and bending over himself and snapping sharply back into place.

His mind clears but his vision's still oddly cloudy and he rubs at his eyes before he remembers. Right, glasses this time around. He digs for them in the uncharted depths of his breast pocket, then in the right coat pocket, then the left.

"What the bloody"- and that's Donna. He turns, seeking out a blob of colour that looks like it might have ginger hair.

"Oh my-." The exhalation to his left is Rose, and the fearful confusion shading her tone makes his adrenaline surge, makes his muscles string up tight, makes his hearts pound triple-time. Never done with the danger, he supposes, especially with Rose back in the universe. She's barely around five minutes (not that he isn't glad of it, of course) and the world's almost been destroyed twice over.

"What?" he finally manages to grind out as his vocal cords snap back into existence and he fumbles his glasses onto his nose. "What are you two on abou-"

And he stops.

And he stares.

At himself. Standing about four meters in front of him, brown eyes blinking back through glasses he's just fumbled on as well.

For an instant the Doctor's sure he's been body-swapped; wouldn't be the first time, after all. But when his hands clutch convulsively at his chest in an attempt to identify the body he's currently occupying, they come up with a handful of familiar brown pinstripes. He can feel the mole between his shoulder blades, and his fingers dart up to check for sideburns.

Yep, definitely still in his body.

Which is very, very bad.

His doppelganger has both hands fisted in his hair, most likely checking the length and texture, and from the stymied look on his face has just reached the same disturbing conclusions he has. The Doctor reaches out with his mind, feels the other man reaching as well and their thoughts brush over and across each other. He flinches at the recognition, and that warm, shivery Time Lord knowing flares brightly from somewhere in his cortex. There goes his last best hope of some sort of cloning accident.

"Oh, crackers," says the man wearing his body.

***

"So you what, got cloned?" Rose and Donna stand somewhere in the vast neutral space between the two of them, both looking utterly lost and very small against the looming limestone walls of the dusty quarry. "Like the people in that hospital on New Earth, yeah?" Rose squints; he can almost see her funny little human brain grinding away and it would make him smile if the situation weren't so immediately, immensely dire.

Her face falls a bit as the wind whips strands of blonde hair around her chin, and he thinks she might be remembering Cassandra's clone, tattooed and pale and dying in her arms. Clones aren't generally built to last. The fear shivering around her eyes when he catches her chin gently confirms it; she's seeing the death of something with his face, with his eyebrows and his teeth and his ears.

"Not cloned," he reassures her.

"Then how the bleeding hell are you standing in two places at once?" Donna's edging into hysteria now; in her defense, it's been a trying day. Saving the world and all. "Time travel? One from the past and one from the future or something?"

The other Doctor rises smoothly, satisfied with what appeared to be a close inspection of his shoelaces. "Not as such, no. More like doubled. Not twins, not clones, not parallel versions of myself, but the exact same person, made up of the exact same atoms vibrating at the exact same frequency at the exact same point in their temporal existence, occupying our space-time twice."

Donna stares at him.

"In other words," not-him amends, "the TARDIS bollocksed it. Got a bit overzealous, I'd imagine."

Rose's eyes dart uncertainly between the two of them. "So which one of you is the real Doctor?" and he sighs, because he knew this was coming and he's not quite sure how to give her the answer she wants. Humans, with their silly, desperate need to define everything, to divide it all up, label it neatly and file it away. He loves them for it, but it makes these sorts of explanations a bit more difficult.

"We both are."

"Well," his other self adds unhelpfully, stretching the word out a bit longer than necessary. "Neither of us are, if we're going to get technical about it."

The Doctor can't help but roll his eyes. Does he always sound that smugly condescending? "Oh yes, thank you, linguistic precision is exactly what we need right this moment."

His reflection quirks an eyebrow, nudges Rose conspiratorially with an elbow. "No need to get snappish," and the Doctor can't help but feel a bit put out when she gives the other him a hesitantly amused grin. He's about to protest when something tickles at the corner of his mind.

The other Doctor stiffens just as he does, his gaze suddenly very far away. "Do you feel that?"

He does, and he lets his eyes drift shut as he opens his senses to the universe the way they used to practice every morning at the Academy, all those centuries ago. Tiny waves ripple in the space between them, the fine-spun threads of reality snagging and pulling gently out of the tightly woven fabric of space.

"Oh, this is bad."

"Very bad."

"Very very, even," and they grin at each other, caught up for an instant in the strangeness of it. He's met himself before, but never without the knowledge that he'll one day be on the other side of the exchange. He thinks he likes this new uncertainty.

"Oh, honestly!" When he turns his attention back to her, he can tell Donna's mustering all of her considerable severity. Of all the people he's ever taken a jaunt around the universe with, Donna Noble is surely tops in severity. "This is the stuff of my nightmares, I'm telling you, Rose. Two of him! We'll never hear sense again."

"Well, I doubt you're going to have to worry about that for much longer," the other Doctor replies distractedly, head tipped as if listening, "as either one of us leaves or the Universe collapses. It'll be back to sense in no time."

Rose whips about. "What? What'd you mean, leaves?"

He grins now because he'd almost forgotten this, her mysterious, boundless concern for him. Silly wonderful things, humans are. It tugs at something deep inside and he reaches out, strokes her shoulder carefully with fingertips. "The same person can't be in two places at once, not at the same point in their linear timeline. Not quite a paradox, but wrong all the same. We're unraveling things bit by bit, just by standing here."

All swirling coat and agitation, the other man paces back and forth in the dust before them, fingers of one hand twisting in his hair. "How long do we have, d'you think?"

The Doctor worries his lip, contemplating, and Rose's fingers slip hesitantly down to tangle with his. Her hand is warmer than he remembers but the gesture is achingly familiar all the same. "A few hours, maybe. I wouldn't push it."

"Another time? Drop one of us off a few millennia away?"

He considers. "Don't think it'd be enough. Still two of me in the universe, operating on the same timeline. Temporal distance might slow the damage down-"

"-But not stop it," the other Doctor finishes, lips pursed tightly in thought. He grimaces unpleasantly and the Doctor makes a mental note to make that face less often when with company. It's not at all flattering. "Please, not E-Space again."

"Oh, no thank you." He ponders a bit, and then his fingers are snapping of their own accord. The sound echoes sharply off the canyon walls, snapping snapping snapping up into the growing dusk. "Pete's World."

"Pete's World!" Hands in his hair again, and the other Doctor spins victoriously out of the circles he's pacing around Donna.

"Pete's World what?" Donna asks, to her credit sounding only a little cross.

Not-him waves an bony, imperious hand in her direction, and the Doctor can't help but wonder: is he really that skinny? He doesn't feel that skinny. He feels quite solid, thank you very much, but this other him looks like he might blow away if the wind picks up again. He's reminded forcibly of a very tall noodle. A very tall noodle wearing a suit, and he certainly doesn't feel much like a noodle at all.

"One of us goes through the rift, to the other universe," the noodle tells her. "Problem solved, universe sorted, and everyone home in time for tea." He pauses, running a considering hand over his lips. "Well, tea-time tomorrow, I suppose. We've already had tea today."

The Doctor can't argue with that bit of logic, and they need to pick all this up a bit if they're going to accomplish what they need to without the knock-down drag-out that's sure to occur once Donna and Rose wrap their heads fully around the situation at hand. "Excellent, yes!" and he tries his hardest to infuse his voice with bright cheerfulness to mask any vocal indication of the sick dread currently bubbling merrily somewhere below his stomach. "Best be off then, pan-dimensional rifts wait for no man," and please, please, please not me not me don't let it be me.

"Right," not-him agrees with nearly-convincing joviality, and their gazes connect just for a second and the Doctor can see all the knowing stretched out there between them, that recognition that one of them has a future, a lovely bright one traveling though all the wheres and whens of the universe, ricocheting gleefully about with Rose and Donna and the TARDIS. Yes, one of them will get a future and the other will get a prison, a prison with walls made only of time and space but a prison nonetheless.

And when you really get down to it, a cell built from the years of a life is much harder to wriggle your way out of than one lined with granite and limestone, sonic screwdriver or no.

"Wait a mo'" Rose says into the silence, and his shoulders slump because he knows Rose, so he knows that any chance they had of making this easy just flew out the window. "Two Time Lords," and she enunciates the words very slowly; they hover in the air, catching and pulling on the tiny rips in the fabric of time. "Two Time Lords, and one TARDIS."

"Um," his other self replies eloquently.

Donna's caught the scent now, and she spins around to stare him in the face. Terrifying, she is. He reminds himself not to cower. He's a Time Lord, for Rassilon's sake. "What, so we're supposed to abandon you? No ship, no nothing? I don't think so, Sunshine."

"It's got nothing to do with you!" he blurts, feeling a tiny bit peevish in spite of himself. "It wouldn't be with nothing; we'd leave supplies. What do you think I am, a barbarian? And what makes you so sure that I'm the one we're leaving behind? It could just as easily be him." He scrutinizes the other man. "Looks like he'd be quite fond of zeppelins, actually."

Not-him rolls his eyes. "Fiddle. We look exactly the same."

"Oh hush." Rose's arms cross stiffly over her chest. "We're not just dumping one of you off in another universe, sorry. Been there, done that, and it's utter bollocks." The sad little twist in the turn of her lips sets off a wave of momentary guilt and there's nothing he hates more than guilt; it makes his stomach go all squibbly.

"Well, I'd love to hear your brilliant ideas," and he's going to blame the unnecessary sarcasm on the squibbly feelings, oh yes. It's got absolutely nothing to do with how off-balance he still feels in her presence, with her hair and her eyes and her lips that he's only seen in dreams for so long now. It has nothing to do with how badly he wants to touch her right this instant, impending end of the universe be damned.

She ignores the defensive bite in his voice, meets his eyes levelly with a challenging look and he's struck by the changes in her; she's still his Rose and yet utterly unfamiliar, still bright and silly but with a new, hardened archness that he doesn't quite understand, that doesn't seem to fit right over her skin.

"I'll go with you, of course."

He looks at her, standing straight and sure in the hazy dusk, and his tongue is suddenly very heavy. "What?"

"Well, if you can't have the TARDIS, at least you won't be all on your own. 'Sides, I was starting to get used to the zeppelins. And Mum and Mickey'll be pleased."

The Doctor can only hope the look on his face isn't nearly as stricken as the look gracing his double's. The TARDIS or Rose. No perfectly lovely future for either of them, after all. Back to the same old life, a bit lonely but free, or be locked away in time with a woman he- -well, he doesn't dare think it. And his life had been looking so bright at tea-time.

"That's…" and the other Doctor's voice peters off. He clears his throat, pinches his glasses back onto the bridge of his nose. "-very thoughtful of you, but not at all necessary," and because they're one and the same, the Doctor knows that when the other Doctor shoots him that sidelong glance it's because he's considering the logisitics of manhandling him through the rift and jetting off with both Rose and Donna in tow without so much as a good-bye. He knows that's what the other Doctor is thinking because he's working through the exact same scheme at this exact same moment.

From the very serious look on Rose's face, this plan will probably require lashing her to the TARDIS console. He's quite sure he filed a nice, sturdy length of rope under "R" in the appropriate chest, alongside Rattigan and Rassilon and Rowling. She's frowning at him now with startling perception, and he wonders idly if she's possibly become slightly psychic during her time in the other universe.

Yes, he's definitely going to need that rope.

***

There is a great deal of arguing and noise and arm-waving after that; Rose against two Doctors, Rose and a Doctor versus the other Doctor, and finally a Doctor going head-to-head with a Doctor while Rose and Donna look on from the sidelines.

"I'm staying with the TARDIS. It's my ship just as much as yours, thanks."

"Fine. Rose and I will have a brilliant time in the other universe, then."

"Well if you're going to be like that, take the bloody TARDIS. See if I care."

"OI." They both turn to stare at Donna. "Since everyone's clearly gone bonkers, I'm in charge and we're going to listen to me now."

***

In the end, the decision is so very simple. The rest of his life, decided by the flip of a coin.

"Call it," Donna tells the other him with a great deal less sympathy than the Doctor thinks the situation calls for. The man looks for a long moment, over his shoulder at the TARDIS and then back at him. His eyes glint, catch the light like Andolosian steel.

"Tails," the other Doctor replies finally, "means he goes with Rose and I take the TARDIS."

Donna nods, rolls the coin she'd dug out of the depths of her jacket around her fingers. He steels himself, tries very hard not to look at Rose, quiet and waiting off to their left with her fists shoved deep into her pockets. He's not quite sure what he's hoping for.

The silver pound spins up into the air, and a small, traitorous voice at the back of his mind whispers Heads, oh please let it be heads.

Queen Elizabeth smiles up at him from the dust.

***

They tramp silently back to the TARDIS, moon now hanging high above them in the sky. The other Doctor disappears immediately into the depths of the ship, muttering something about supplies and saying good-bye, which leaves him standing awkwardly with Rose and Donna in the main control room. He's not sure what to say, so he busies himself at the console, throwing switches and levers to get them back to the spot where Rose had popped into this reality earlier this morning.

"Very odd place for a rift," he starts, if only to escape the highly uncomfortable silence. "Right next to the shark tank. Do you think there's some significance to it?"

"What, like carnivorous sea creatures have some sort of destabilizing effect on the universes?" she asks from very near his shoulder, her breath brushing his neck and her voice thick with unshed tears. "Could be."

He turns abruptly, accidently bumping her nose with his shoulder, and he catches a glimpse of Donna escaping quickly into the hallway. "You don't have to go," he tells her, trying not to sound too desperate because he's got the TARDIS and his freedom, but he's suddenly not at all sure it's everything that he wants. "There's still so much for you to see. The scarlet jungles of Elsaltia. The golden cities of Frappis Prime." She says nothing, head tilted up to watch his face. Her eyeliner's starting to smudge and oh Rassilon, he's just gotten her back and he's never going to see her again. She's never again going to smile at him or roll her eyes or punch his arm or eat the last of the biscuits without putting them on the shopping list. "He'd understand. I would understand."

Her eyes are dark and deep. "I couldn't. I couldn't live with myself, knowing that you were out there all alone."

"Right," and there's a very odd feeling in his chest that he doesn't like at all.

"You'll be all right, yeah? You and Donna and the TARDIS, having a right laugh," she tells him, voice wavering only a little. "You've got a whole universe to see. Tomorrow'll be just the same as yesterday."

He doesn't know what to say to that; wrapping her in a tight hug seems as good a response as any. She clutches at his jacket, buries her face in his neck and he tries to memorize how she feels against him, tries to burn the smell of her hair into his brain. This is such a different goodbye, he thinks desperately, because he ached so much that first time on the beach but he could convince himself his sorrow was for her, for leaving her trapped where she didn't want to be. This time, Rose will have a Doctor like she wants and he won't be able to pretend the hollow throbbing in his hearts isn't purely selfish.

The embrace breaks when they're bounced violently against a nearby lever; the TARDIS heaves and groans as is settles into their destination. He can feel something like displeasure at the back of his mind; the ship is as unhappy with this development as he is.

"We're there, then?" the other Doctor asks carefully from the entryway, his trans-dimensional pockets bulging at the seams. The Doctor doesn't want to contemplate how many of his things he'll find missing later, though he supposes he really isn't in any position to complain. He'd want all the gizmos he could carry as well if he were the one about to be stranded without a time machine on twenty-first century Earth, Rose or no Rose. He realizes he's staring at the other man's trainers, avoiding his face on instinct alone. Eye contact with oneself is a bit jarring when not standing in front of a mirror. He forces himself to look up.

The other man looks oddly grey as he crosses the room to stand by the console on Rose's other side. His fingers stretch out to gently stroke a nearby panel, a farewell to his oldest friend, and the moment is so intimate the Doctor can't bear to watch. "I'll just go find Donna so you can be off," he blurts, choking a bit on the words, and nearly trips over the grating in his rush to escape.

***

He doesn't look for Donna at all, instead wanders the hallways and wonders what it would be like, saying farewell to his ship, to this place that's been his home for nearly all of his very long life. His only constant for so many years.

His hands brush affectionately along the decorative molding on the wall, trace the fading patterns of the wallpaper. He doesn't recognize this hallway; he's almost certain he's never seen it before in his life. Perhaps it's new, made just for him to wander and feel melancholy in. The wood paneling is exactly the right shade for melancholy.

"I'd never want to leave," he tells the empty hallway gratefully, "absolutely never. It's just…"

The wood warms slightly under his hand, and he knows she understands.

***

When he finally returns to the console room with Donna in tow, the other Doctor is looking a bit less gray. His eyes are wet, and so are Rose's, and the Doctor tries not to notice their tightly clasped hands. Better not to think about it, he tells himself. Better not to dwell on what might've been.

"Well then," he says, and the four of them walk out the TARDIS doors and into the darkened halls of the National Aquarium in Sydney. A hammerhead glides smoothly by behind the glass, and the other Doctor drops Rose's hand, moves to make his goodbyes to Donna. The Doctor finds himself again faced with Rose.

"So," she says, sniffling discreetly behind her hand. "Take care of yourself, yeah?"
He nods, not trusting his voice. She is lovelier than he remembers her being, her face older and her eyes wiser. She steps closer to him, tips her head up for a kiss but he can't, he just can't open that door again so he dips his head, presses his lips very softly against her forehead instead.

"Have a brilliant life," he manages, and then Donna is beside him again, fingers squeezing his elbow, and Rose and the other Doctor disappear through the rift in a fizz of static and metallic tang.

He turns sharply on his heel, escapes back into the TARDIS. Donna is snuffling into her sleeve somewhere behind him. "You're a bit of all right, you know," she says and he wonders what his other self said to her. All sorts of sappy things, no doubting it, and now she's going to treat him like her favorite puppy for at least a week.

He begins jabbing buttons on the console with a bit more force than necessary because he suddenly wants nothing more than to get far away from here, to forget this entire messy incident happened at all.

Silence hangs heavily over them. When he looks up, Donna is watching him, mouth soft and downturned. "I'm sorry," she tells him quietly.

He grabs a lever, jerks it upwards as hard as can. Something inside the panel creaks dangerously. "Don't be. I kept the TARDIS." He grabs the mallet, closes his eyes and lets himself harden. "I won." The impact echoes through the ship; the rotor wheezes in protest.

It's the truth, even if he's not quite sure he believes it himself.

***

He gapes at the lab. "Everything. That bastard took bloody everything.

Donna raises a skeptical eyebrow at the remaining technology cluttering the benches. "Plenty of junk still here, if you ask me."

"Exactly. Junk. He took everything worth having! The neutron flow converter, the plasma transmogrifier…" He trails off, remembers that he wasn't wearing his coat when he was doubled. He checks his pockets desperately. "He took my screwdriver!"

"There's five screwdrivers sitting in the basket right in front of you."

"But he's taken the good one, the one with all the new modifications! I spent ten years perfecting that one. Ten years!"

Donna just looks at him, unimpressed. "Well. Suppose you better get cracking then."

And he does, grumbling all the while.

***

Time passes. They find lots of trouble.

They help UNIT save the Earth from an invasion force of telepathic salamanders; after they've blown up the satellite broadcasting the mind-control signal, Martha invites them both to her wedding. The Doctor very nearly refuses the invitation, but assents off Donna's look. Once they make it back to the TARDIS, the Doctor stalls as much as he can but Donna's not having it. He hates weddings, depressing, stuffy things that they are.

"Let's go today," she says, a little over a week later. "You said yourself you're not in the mood for hiking so the mountains are out, and I could really go for a nice piece of cake.

"Why are you in such a hurry? We've got a time machine. We could wait fifty years and still 'make it to the church on time', as they say."

Donna narrows her eyes; she's cottoned on to his tricks in a way so many of his traveling companions never did and as much as he likes her it's a bit annoying, really. "Yeah, but then when you accidently run into her future self and we haven't gone yet than you've forever missed the wedding and you'll be in a world of trouble."

He tries not to grumble; he swears to himself that the next person he asks to travel in the TARDIS is going to be exceedingly stupid.

So they get all dressed up (Donna fusses with her hair for ages) and he stands in the back of the church and thinks about how much he truly detests weddings, especially his own.

He has a troubling thought as Martha is reciting her vows; there's another version of him running around on another Earth and living a very humanish life. What if the idiot goes and does something stupid like getting married again? He tries to imagine it, a human ceremony in a church and him waiting at an altar very much like this one. When Rose appears in a wedding dress, he starts to feel very, very itchy and more than a little nauseous.

"D'you think they'll get married? Him and Rose, I mean?"

Donna stares wide-eyed, and perhaps he spoke a bit too loud for the middle of a wedding ceremony; several heads turn to look in their direction. She steps on his foot very hard.

"Ow!" More heads swivel, and he shuts his mouth determinedly.

"No, I really don't," she hisses at him under her breath, "because I can't imagine a universe where a woman in her right mind would agree to marry you."

He considers that. "Yes, but can you imagine a universe full of zeppelins?"

She blinks. "What?"

"Exactly."

***

Martha hugs them both endlessly in the greeting line, genuinely glad they came. She introduces them to Tom, who seems sharp and just the sort of man Martha should be marrying. ("Find me one of those, please," Donna murmurs to him after shaking the man's hand). He gets a bit depressed after the toasts because he keeps having highly unsettling visions of himself and Rose shoving cake gleefully into each others' faces, so he eats all the shrimp and about 35 bacon-wrapped scallops at the reception and makes himself violently ill.

Donna notices, likely susses out what's wrong as she tends to do, and is uncharacteristically sweet to him for an entire week after the wedding. She makes tea every day, which she never does, and in a last ditch to cheer him up makes four batches of lemon bars, which he adores. He adores lemon bars, but he detests being mothered, so after she goes to bed he eats all four batches in one go out of spite and is violently ill yet again. She stops being nice after that, and lets him bang all the doors on the ship to his hearts' content until he gets bored with it, which only takes about three days.

***

Time passes. They find lots of trouble.

***

They visit a lovely little market in a town in 19th century Gloucestershire to pick up some milk because the Doctor drank the last of it with his tea and didn't leave any for Donna. Through a convoluted series of events involving Donna posing as a milkmaid and the Doctor having a big mouth and no mental filter, they end up discovering vaccination with Edward Jenner completely by accident.

After that, they catch the 235th Annual Interstellar Regatta in the Betazoid system and become unwilling participants in the race when protestors hijack their observation boat. The Doctor foils the plot of a terrorist cell of xenophobic Dolvians who hope to sabotage the hard-won peace in the system, and Donna, very much to her own surprise, takes second place in the regatta and goes home with a very large, very shiny trophy. The TARDIS makes a trophy shelf in the library just for her, complete with a little plaque that reads "Donna Noble," which makes the Doctor smile and stroke the console even more than usual.

***

Time passes.

They stumble into a bloodless revolution; Donna falls in love.

***

His name is Taxxeiseid; he's one of the university professors who helps them lead the student uprising on Bastenia Majora. She calls him 'T' because she can't pronounce his name. They are perfect together, even if his skin is a bit green and clashes horribly with her hair. They fit in a way that hurts him, mostly because it makes him wonder if he himself is currently fitting that way with a certain someone in another universe.

The Doctor finds it very difficult to feel put out when she tells him she's staying. He always knew she would leave someday and he can't help but be proud that she could find her happiness on a planet other than Earth. She tells him they're getting married that very day so he doesn't have a chance to escape because she wants him at the wedding and she knows that if he leaves, even for a minute, he's never coming back.

He laughs. "You've got me pinned, Donna Noble." He hugs her, kisses her cheek.

And he slips away while she isn't looking.

***

The day after he leaves Donna, he sets the TARDIS on the randomiser. When the doors open, he steps out and directly into a pile of brooms, which fall and clatter and hit him repeatedly in the face. She's landed them in a very small supply cupboard. "Oh, ha ha. Hilarious."

But he goes out exploring anyway because that's the whole point; he escapes the brooms and the cupboard and finds himself in a sprawling, cluttered factory. 76th century, somewhere in the Human Empire, he guesses. The air hangs heavy and sticky-sweet and there's an odd sort of tinkling in the air, like hundreds of thousands of wind chimes all swaying together on the breeze. A bottling plant?

There's a bored-looking humanoid pulling a lever over and over just down the way; the Doctor jogs over to him. "Excuse me, but would you mind telling me what sort of factory this is?"

The man blinks four very round eyes at him, and very obviously decides the Doctor is an idiot. "It's the Lippman plant. Clearly."

The Doctor blinks. "Not…" and he does the temporal math very quickly in his head, "Lipmann's Old Time Jams and Jellies? Lipmann's Old Time Jams and Jellies, the best jams and jellies in the entire Beta sector?"

"That'd be the one."

He swallows very hard, tries not to burst into delighted laughter because yes, Donna Noble was brilliant and wonderful and stayed for ten years, longer than anyone's stayed ever, but he's still got his best mate by his side, his very best mate in the entire Universe, his glorious, brilliant ship.

"I don't suppose there's some sort of factory tour? A tasting tour, perhaps?" Please say yes, he thinks, because he's not in the mood to get chucked out by security after he's dipped all his fingers in the vats of boysenberry jam.

"Tourists," the man wheezes softly through his small, sawed-off tusks. "The sign-up for the tour is up that hall, right next to the little shop."

***

Time passes. Companions come and companions go. He snogs Moon Princesses and scales volcanoes and sees stars and moons and black holes and brown holes and even a few yellow ones. Every day is different and yet, every day he feels the same. Every day he wonders; what if? Not that 'what if's' are at all unusual for Time Lords; every thought, every moment of his existence is filled with what ifs and maybes and possiblys and 'what could go wrong if I press this lovely red button?'s.

It's just.

It's just that all the "what if's" in his life that don't come to pass generally stay firmly in the hypothetical. But in this case, in this one very strange and inconvenient case, the hypothetical is definitely not hypothetical at all, is definitely living on a planet full of zeppelins, quite possibly with a job and a house and a mortgage and a car and taxes and a wife named Rose Tyler.

And he's really not sure how he feels about that.

***

Martha calls him back periodically to help UNIT get themselves out of whatever stupid scrape they've bungled their way into. He hasn't had anything like this for a long time, a friend that he sees on and off, now and again. He's never quite sure why he's broken his own rules about repeat visits with Martha, but it's not going too badly so he doesn't question it.

He comes when she calls and helps her blow something up, and sometimes, after the explosions, they have tea and biscuits and they catch up a little. He watches her grow and mature and change into an elegant, capable woman and on the whole, all this aging stuff isn't nearly as bad as he thought it might be.

One day, he steps out of the TARDIS onto Martha's street, expecting a battalion of soldiers and smoking rubble and desperate, screaming mobs of people (the usual scenario preceding a call from Martha) and instead finds the tree-lined neighborhood quiet and empty except for Martha and two other people. Two very small people.

"I know you don't usually do these things," she starts very quickly, "but they wanted so very much to know you."

He blinks, looks down at the two children who are undeniably Martha's. They don't look at all like Martha in miniature as he sometimes lets himself imagine people's children, but he can see something of her in each of them: her unflinching nerve sleeping in the girl, her startling intelligence hiding behind the boy's eyes.

"These are my children," she says and he nearly smiles at how nervous she sounds. "Peter and Lily."

He looks down, pushes back memories of his own children, pushes back wonderings about small blond children his other self might be playing with right this instant, and considers them. They say nothing, simply stare wide-eyed and guileless back at him, and the Doctor finds, very much to his own surprise, that he wants to know them too.

***

Time passes, as it does, and the Doctor wonders.