The only reason for time is so that everything doesn't happen at once.
- Albert Einstein

"So," Rose said, eyes on the central column of the TARDIS as the piston slowed to a stop. "Where are we, then?"

Jack grinned and bounded over to one of the console screens, tilting it up towards him to study it for a moment. "Well... according to this, we should be just about-"

"When did you learn to read that?" the Doctor asked with a frown, straightening from where he'd leaned over the console. Jack chuckled and stepped back from the console again, hands raised in surrender.

"I didn't, actually. I just counted on you interrupting me right there anyway - might as well sound like I know what I'm doing in the meantime."

The Doctor reached over to cuff him lightly on the side of the head, though he smiled as he did, and Rose laughed, which was exactly what Jack was going for in the first place.

"You're impossible, do you know that? One of these days, I'm just going to stop listening to you."

Reaching out with one hand, Jack caught Rose around the waist and pulled her to him, prompting a startled giggle from her. "Well, until then..."

"Until then," Rose said, twisting around in his arms to face the console, "I still want to know where we are."

"Cardiff," the Doctor announced, flipping a switch or two on the console without looking up. "Some time in 2007, unless we've gotten a bit lost, but definitely Cardiff."

Jack raised his eyebrows. Rose, leaning back against Jack's chest with his arms around her waist, looked dubious, which made Jack feel better about his own skepticism. "Doctor?"

The Doctor glanced up briefly, then back down at one of the screens on the console, which flickered with Gallifreyan symbols Jack had yet to decipher. "What?"

"What's in Cardiff?"

"The rift!" he answered brightly, as if that explained everything. Jack, who over the course of countless missions with the Time Agency and many cons on Earth had (to his knowledge) managed to avoid ever setting foot in Wales, did not find this a satisfactory answer.

"Great. What-"

"But we closed the Rift," Rose interrupted. "I mean, Gwyneth did, and that was over a century ago. Why would it still be here?"

"Oh, it's closed, not gone. And in the meantime, it's leaking energy we can use to fuel the TARDIS."

Rose's expression only grew all the more skeptical. "You're joking."

The Doctor punched a button, frowned when nothing happened, and reached for the mallet he kept beside the console. "Did you think this ship ran on hope and happy thoughts?"

"And you mocked me for needing batteries," Jack muttered softly to her, smirking a little. Rose elbowed him, rolling her eyes and pulling away lightly.

"How long are we going to be here?"

"Ah..." The Doctor looked up thoughtfully at nothing in particular, unless somehow he thought he was going to find the answer somewhere in the intersecting columns of the TARDIS. "A couple hours, at least. You two should go on, wander around... by the time you get back, we'll be ready to go."

"Oh, yes, who could resist the opportunity to wander around Cardiff?" Jack muttered under his breath.

"The last time we were here, we met Charles Dickens," Rose informed him brightly, scooping up her jacket from where she'd draped it over a railing and bouncing toward the door the way she always did, whether they'd landed some time in the Middle Ages or her own time period or some time in the far-flung future.

"Do you think that's likely in 2007?" Jack asked as he followed her. He couldn't really help himself. Rose started off, and he followed, not least because there was the vague concern in the back of his head that if he didn't follow her, if she wandered off alone, she might well end up dangling from a barrage balloon again. Well, probably not exactly that, especially in this time period, but there were any number of situations she could get herself into that didn't involve barrage balloons.

"Probably not, but... things could happen."

"In Cardiff."

"You never know," Rose pushed open the doors to the TARDIS - and then stopped abruptly to turn around, Jack nearly running into her as a result. He almost tripped over his feet attempting to not run into her, and covered by side-stepping, leaning against the door frame, and crossing his arms over his chest. He had a feeling it didn't work quite as well as he'd hoped.

"Aren't you coming?" Rose asked the Doctor, who still stood by the console.

"Oh, no." He waved them off with one hand without looking up. "I'm going to stay here and make sure the Rift doesn't do anything strange. You two go on."

"Are you sure?"

"Absolutely. You'll be fine. It's Cardiff, in the year two thousand and seven. What do you think's going to happen without me?"

Jack groaned and banged his head lightly against the door frame he still leaned against, closing his eyes. "I really wish you hadn't said that."

Jack flopped into his chair, more falling than sitting, and glowered at the calendar on his desk, like it might have maliciously placed itself there. In reality, it was probably Ianto who put it there - he seemed to think Jack needed the reminder, and every time Jack tossed out a calendar, a new one would discretely appear on his desk within the week. Jack was far more aware of the passage of time than Ianto could understand, and he didn't need to be reminded. Especially not of days like this.

He reached over to knock the calendar on its face and then switch on the CCTV monitor beside his desk. The screen flickered in shades of green and black before settling into the image just above the lift, and the TARDIS sitting directly on top of it. Jack stared for a second, his chest aching, before leaning forward again to turn it off. The picture faded back to black.

Outside his office, there was a thump as Owen set down a bag on the floor by his desk - Jack didn't want to know what Owen was carrying around to make that sort of a thump - and the distant sound of chatter as Tosh said hello. Jack paid hardly any mind at all, too focused on the presence of the Doctor on the street just above them. But it was the wrong Doctor, he was too early in the timeline and Jack was with him, younger and happier, and Jack already knew he didn't see the Doctor today. He lived through it.

It wasn't like he hadn't done this before. He and the Doctor and Rose had stopped in Cardiff to refuel a grand total of three times before the Game Station. The second time was in the 1940s, and Jack was nowhere near Cardiff at the time, so he hadn't had anything to worry, though he spent the entire day quiet and uncommunicative, staring at the sky and trying not to think of the future, his past. It was a quiet day, in the middle of the war, and he kept hoping that someone would start shooting at him, because even that would be better than having the time to think. The third time was a little over a year ago, with the mayor and the earthquake, and he spent the day locked down here, forbidding his team to leave the Hub if the world was ending. The first time was now, and it occurred to him that he should give his team the same warning now, because if they left and bumped into his younger self...

With a sigh, he levered himself out of his chair and started out of his office, into the main atrium. Gwen looked up at him as he stepped through the door. Owen, busy taking his time starting up his computer, and Tosh, staring intently at her own computer screen, did not. Jack reflected that he really needed to work on his commanding presence - he used to be able to just walk into a room and have everyone looking at him, immediately. Of course, back then, he didn't usually spend enough time with people for them to get used to him... Still. It was something he'd have to look into.

"Alright, first things first - no one's going anywhere today. No one is leaving the Hub until you all go home for the night. I don't care if-"

"Jack?"

Jack grimaced at the interruption - so much for commanding presence - but turned toward Tosh nevertheless. "Toshiko. This had better be good."

"It is. I think." She gestured vaguely to the screen, frowning a little. "There's a police report that I think we should-"

"I was just saying we're not leaving the Hub unless the world's about to end," Jack said quickly, before she could continue. "Police reports don't qualify." Whatever it was, they could deal with it later. When the Doctor and Rose and a younger version of Jack weren't running around Cardiff.

"Jack," Tosh said firmly, shooting him a frustrated look over her shoulder. "It's from Aston Lloyd's flat."

He froze for a moment, and then walked over with a sigh, standing behind Tosh with one hand on her shoulder as he stared at the screen. "What happened?"

"Who's Aston Lloyd?" Gwen asked a moment later, walking over to stand at Jack's side.

Owen hadn't moved from his chair, and didn't look particularly inclined to. He flipped a pen absently in his hand, tossing it in the air and catching it over and over as he answered, "Some bloke who fell through the Rift a year ago, from... oh, about ten years in the future? Of course, we got to take care of him, find him a job and a place to stay, all that - more trouble than he's worth, if you ask me. What'd he do now, Tosh?"

"He's been attacked, and he's dead now."

Owen looked as if he were momentarily at a loss for words. "Oh."

Jack sighed. Just what he needed in his day. "Any mention of what did it?"

"Some sort of animal. The report wasn't any more clear than that, but I did find a CCTV feed by Aston's building, and..." Her fingers flew across the keyboard, too fast to see any individual keystrokes, graceful and assured, and in a moment an image popped up on screen, still for a second before a tap on the keyboard started it playing. Jack leaned in, studying the video. Just an image of an empty street in the middle of the night, streetlights and the fronts of a few buildings, cars parked on the side of the street... Nothing of any particular interest.

"So what-"

He stopped. Something dark and solid had flickered across the screen, too fast to recognize it, but something about the shape of it, half-registered, set off alarm bells in the back of Jack's mind, some ancient half-remembered threat...

"Rewind that and play it back frame by frame."

Tosh set it back thirty seconds and clicked through each frame individually. Nothing... nothing... still nothing... and then a blurry shape, which within a few frames resolved to a clearer image of something very obviously not from Earth. Four-legged and lean, a thin body slung on even thinner legs, shoulder blades jutting up sickeningly from the body itself, each coming to a sharp point that slanted backwards. A spiky ridge along its back, and a narrow serpentine head, no tail or ears, all in all like some sort of twisted greyhound. Jack stared at it, willing himself to remember.

"It's on the video twice," Tosh said as she clicked through a few more frames. The creature's gait, even in slow motion, made Jack a little sick to look at, like all the joints didn't quite fit properly. "Once here, at about three AM last night, and then again twenty minutes later, just after Aston's estimated time of death on the police report."

Jack stared at the screen a moment longer, memory tickling the back of his brain. With his luck, it would be something from the two years he lost, something he knew he ought to know but just couldn't put words or images to... A moment later, the image clicked with a name in his mind, and he let out a breath of mixed relief and annoyance. Of course that thing had to be here the same time as the TARDIS and the Doctor and...

It couldn't have waited a day? A few hours, even... No, it couldn't be that easy, could it? Not for him, not on a day like this.

"I guess we are leaving the Hub today, then."

"End of the world?" Owen asked, eyebrows raised.

"Close enough."