The Doctor wakes in a British home in 1940, with no memory of how he got there. He finds himself at breakfast with a household of interesting characters and realises they're being menaced by an alien intelligence. He teames up with the landlord's son, young Robert Mann, who definitely knows he wants to be something he grows up, even if exactly what changes every twenty minutes. They asks for the stories of the other residents, and the Doctor determines that someone is sapping their ambition. Robert guesses that the Doctor is an alien, because only an alien would have something like the sonic screwdriver, which he swiped from the Doctor's pocket last night.