Meanwhile, four months in the future and 150 miles to the east...
"We could have been so good together!" Christina called to him, her red double-decker bus hovering just outside the TARDIS.
"Christina! We were!" he replied, exchanging farewell smiles with her. He watched a moment as she took off, then stepped inside his TARDIS.
He walked to the console slowly, hands in his pockets, eyes cast downward. Carmen's words drifted through his mind: Your song is ending, sir. It is returning. It is returning through the dark.
"Nah... Low-level psychic, right?" he announced suddenly, discarding his coat and dropping it on the grated floor. "What does she know? Still plenty of verses left in this song!"
He patted the console, beginning to adjust controls. "So, old girl, when shall we go next? Maybe another holiday," he mused. "We did Christmas... Now, Easter... Hey! No. No, never mind. I don't have anything green..."
He contemplated the Time Rotor a moment, then grinned broadly. "New Year's! We didn't celebrate the new year... Might as well go back and catch that one." He flipped switch and levers, programming their trip. "Let's go visit Jack. And Ianto, of course. Plus, that way I'll have a chance to do a bit of research on that Malcolm fellow. And possibly, forewarn them about a flying bus..."
He threw the Dematerialization Switch. "Allons-y!"
Seconds later, the TARDIS began to rematerialize. Alarms immediately blared.
"What?!" he exclaimed, utterly confused.
He dashed around, his brow becoming increasingly furrowed as he examined displays and monitors. Several laps around the console later, the TARDIS abruptly changed course, rematerializing just outside Torchwood's 'Tourism' office.
"Good thing the shields were up..." he muttered, examining the data recorded by the TARDIS' instruments. "More of a temporal sideswipe, instead of a full-on collision. But..." He frowned. "That just can't be... That's not..."
He rummaged in his suit pocket and (after setting aside a yo-yo, three peppermints, and some metal items that may have been coins, but could have just as easily been hardware) came to the item he'd been searching for: Martha Jones' mobile.
He dialed a number, holding the phone to his ear as he cautiously exited the TARDIS, glancing right then left.
"Jack!" he shouted as soon as Jack answered, not even waiting for a greeting. He began walking towards the office and, with his voice now lowered to a hushed whisper, he continued, "Jack, I may have something of a problem here... Possibly a very big problem. Maybe... Well, no. I don't think anything will, you know, go boom. But! Either A, I'm already here -- in which case, there is a significant issue with my temporal control -- or two... No. Wait. B, someone else has a TARDIS here, which doesn't make any sort of sen--" He broke off abruptly, frowning, finding the office locked. "And where are you?"