Unfortunately for the Doctor, that request just confuses him. "Well, of course I plan to return to UNIT afterwards," he says. And he frowns, wondering if the Doctor is referring to something that he knows is coming for Will. Still, although he's tempted to fish for more information, he knows better than to do so. "But really, you know much better than I do that travelling in the TARDIS and living in one time and place are rather mutually exclusive," he adds instead.