Minor spoilers for A Good Man Goes to War and Utopia, plus a few things that might make more sense if you've seen Torchwood - not necessary, just adds a little more insight to Jack's history. Plus it's an amazing show and everyone should watch it anyway... but I digress...

One time he'd done this — ages and ages ago, now, back when the Earth was young and he himself was entirely different — the man he sought had quite literally jumped at the chance to travel in this blue police box. Despite being unsure of his reception, the Doctor hadn't been expecting the open doorway to remain empty. He waited… still empty.

Waiting was not a game the Doctor liked to play — certainly not with a man who literally had all the time in the universe to draw him out.

Torn between irritation and impatience (not nerves, thank you, he was not anxious), the Doctor stuck his head out of the doors. Sure enough, there he stood: broad shoulders straightened with military bearing, his hands tucked behind his back and his head high. The simple, crisp black outfit gave no hints as to his current identity, but… this was his place. The Doctor could feel it in the very air around his one-time Companion.

He tipped his head in greeting, but otherwise made no movement. "Doctor."

Resigned, the Doctor stepped out of the TARDIS. "Captain."

He smiled very slightly, almost nostalgically. "I know what you're gonna ask," he admitted. "And I'm sorry."

Impatience won out, after all. "Jack, this is important—"

"It's not Jack," the Captain cut him off, smile completely gone. "Not anymore, not for a long time now. 'Captain' will suffice."

The Doctor met his gaze. Cool, tired blue eyes, once sparkling with mischief and wonder, were now full of age and pain. The face was still the same, mostly: more lines now, the brown hair streaked with pale grey. But it was the eyes which marked the passing of millennia — slowly, day by day, in a way the Doctor's never would. "Still haven't forgiven me?" he asked quietly.

"Never," the Captain said simply. "But that doesn't mean I wouldn't help if I could."

"Then why—"

"Because this is your turn," the Captain interrupted again, voice cool and hard. "Demon's Run," he announced, "the asteroid where you're headed to wage war because that's where they've taken someone you love. Do you know why it's called that?" he added softly.

The Doctor clenched his jaw. "Of course I know."

The Captain's eyebrows rose. He shrugged slightly. "But you're still going."

"I have to!"

"Of course," the Captain agreed instantly. "You have to." Somehow, it sounded different when he repeated the words — not the imperative of duty and friendship, but almost a portent, the simple words weighed down and striking heavily between them.

The Doctor gazed shrewdly at him for a long moment. Then he said, "Why do you say this is my turn? Why won't you come with me? Every other time I've asked you, you've come to fight with me, why not now?"

The Captain sighed. "When we first met," he began, then almost chuckled. "Did you ever think we'd end up here?" he wondered with a wry, tired half-grin.

The Doctor sighed impatiently. "Look, Jack—"

"It's not Jack." His lips pressed into a thin, hard line. "The people who called me that are ones I want to remember, people I loved a long time ago. Too many people saying that name means eventually I'll forget them, let them get washed away by all these years that you forced on me!" His voice had risen, in intensity if not in volume, and his eyes suddenly burned. "Yet all these years, when you snap your fingers I've come running."

His voice lowered to a hiss. "But now, Doctor, now I'm so old. So much older than even you are. I've taken the long path to get here and I have learned things you've never bothered to stop and think about, because you'd rather pretend they don't exist, can't affect you." He leaned in closer — for the first time in three regenerations, the Captain had the advantage of height as well as age, and used it. "But you don't see, Doctor, that this is all about you. What you've become."

He stood back. "And this time I can't help you. This time, you can't have the man who can never die backing you up. This time you won't be able to run away and damn everything you leave behind. You have to know," he finished simply, taking another step away. "This is when you have to understand that everything that happens there is because of you." That wry half-smile twitched his lips again. "Because 'demons run when a good man goes to war,'" he quoted, shaking his head slightly. "As we all should have."

"You don't understand what's at stake," the Doctor pleaded. "Amy, Rory, their daughter, I promised, Captain."

One dark eyebrow rose cynically, but the Captain made no comment on the string of broken promises the Doctor had no doubt littered in his long, long life. Possibly not the best tactic, then. "Please, if you knew—"

"I do know," the Captain cut him off. "Timelines, Doctor. I already know. I understand better than anyone else possibly could. And I am sorry. But it's time for you to leave."

AN: This is the first time I've written the 11th Doctor - or anything strictly Doctor Who, actually. But this episode was too good to pass up, especially after about the third time I watched it and thought, 'wait a second... where's Jack in this gathering of allies? I mean, come on, a coup in deep space and you don't get an immortal Captain on your side?' Then I found out that John Barrowman was originally going to be on it, only to have a scheduling conflict and prior commitments. From there the plot bunnies went wild. Anyway, hope it at least makes sense - feel free to tell me what you think.