Paris, 1942. In the middle of the Occupation, Victor Gence, an unscrupulous merchant, buys, at vastly low prices, artworks belonging to Jewish collectors. Informed by a concierge, he manages to enter the apartment of Mr. Klein who apparently has a fabulous collection.

Joseph has an intensely close and ambiguous relationship with his sister Marianne. At her going-away party the day before she leaves to go abroad, Joseph is caught between his feelings for his sister and the advances by other suitors.