"Oh, laugh a minute, you are! Actually, that's Ianto's office, so he'd be the one you'd check on for brochures. Do you remember where the water tower is?" He walks along further to get himself closer to the landmark. Better be right there on hand when the Doctor sees the second TARDIS, anyway. "I'll be by it."
He's about to retort with another joke when the Doctor's tone changes, and he sobers accordingly. "For what it's worth, then, Happy New Year, Doctor. And I don't think this'll be trouble, but I'm not sure. You'll understand it better than me, actually."