After the outbreak of the Second World War, Margret and Hans temporarily leave Paris for the isolated village of Saint-Mézard. Here, they begin the first Curious George story while staying in a tower at Château Feuga, where they spend the next four months, hosted by their long-time friend, the German doctor Walter Katzenstein. The story, entitled Fifi: The Adventures of a Monkey, recounts the antics of the youngest curious monkey in Raffy and the 9 Monkeys. It was later published in the United States under the title Curious George.
At one point during their stay, the Reys are questioned by the village policeman, their German accents having aroused the villagers' suspicions that they might be spies. Suspicions are allayed when a search of their castle studio reveals only partially written manuscripts and the disarming watercolours of Fifi and Whiteblack, a travelling penguin and the subject of another story the Reys are creating.