"Act 1." Gilberte Valandray (Sabine Azéma) is the socialite wife of rich Parisian businessman Georges Valandray (Pierre Arditi) from whom she has concealed a previous but unvalidated marriage in America, being aware of her husband's belief in the indissolubility of a relationship based on a first sexual experience. Only her spinster sister Arlette (Isabelle Nanty) knows the secret. Secure in her husband's confidence in her, Gilberte now encourages a circle of amorous admirers, as flirts but nothing more, including Faradel (Daniel Prévost), a middle-aged dilettante, and Charley (Jalil Lespert), a young avant-garde artist who is also pursued by Gilberte's young friend Huguette (Audrey Tautou). Gilberte is then aghast to discover that her husband has invited to dinner an American, Eric Thomson (Lambert Wilson), with whom he is about to sign a deal, and who is none other than her first husband. With embarrassment Gilberte appeals to the truculent Eric to preserve her secret.