Having fortuitously discovered a photograph in which Marthe embraces someone unknown, clothed with a chequed jacket, Étienne Dorsay becomes jealous, and imagines various stratagems to identify the lover.In the meantime, Étienne and his friends acquire a weekend house for a very low price.As in the previous work, the film is largely narrated by the character Étienne, whose tone shifts with the reality of the images.The film contains a certain number of allusions to the films of Blake Edwards (the Pink Panther series).