In Paris, near the end of World War II, crotchety professor Fernand Bonnard maintains a zoo and continues his research. He's a coward, as is his debonair son, Armand, who has one daughter, Philippine. On her eighth birthday, Armand picks her up from her repressive boarding school and takes her to Fernand's to celebrate. Father and son quarrel, and Armand leaves, only to be arrested and shot for violating curfew. In grief, the curmudgeonly Fernand does not tell Philippine, but invents a life for Armand as a captain of the Resistance. Fernand takes her from school to live with him and his sensible wife. Along the way, Philippine finds out the truth and Fernand discovers courage.