The Doctor marches off toward the TARDIS, arguing with himself, trying to make himself not notice the flickering streetlights. "Am I noticing? No. And what I'm not doing is scanning for electrical fluctuations!" Naturally, he's got the sonic screwdriver out at this point and is waving it around at the street. "I'm going," he says. "I am through saving them! I'm going away now!" Even he doesn't really seem to believe himself.
Bright and early the next morning, he's at the department store, demonstrating a toy airplane for a gaggle of utterly rapt children. He accidentally steers it into Craig, who's pushing Alfie around in a stroller. Craig is stunned to see him. The Doctor gleefully tells him he's working there now and shows off the name tag pinned to his suspenders. Appropriately, it reads "The Doctor: Here to help." Craig is too exhausted from baby duty to question the Doctor too much, although he does mention the Doctor is missing that galactic alignment. Craig is evidently a good listener. Good catch, Sophie. The Doctor plays with a robot dog for a bit -- even though it's not as fun as his last one -- then sees a little silvery gizmo darting across the floor. Craig pleads with the Doctor to tell him what's going on. His son lives here, he says. He needs to know if there's anything dangerous. So the Doctor fesses up and tells him three people have gone missing from the shop in the last few days. Also, there's that whole thing with the power fluctuations.