1945. London still can’t recover from the war. The parents left the 14-year-old Nathaniel and his older sister Rachel in the care of a mysterious man nicknamed the Moth. They suspect he’s a criminal, and with every discovery about his eccentric friends—men and women who were connected in the past and who now want to look after the young heroes—they become more convinced. But who are they really? Why do they want to care for Nathaniel? And how should brother and sister behave when, in a few months, their mother returns without their father and doesn’t explain anything?