午夜Celestine, the chambermaid, has a new job in the country, at the Lanlaires. She has decided to use her beauty to seduce a wealthy man. But Mr Lanlaire is not a right choice: all the house is firmly controlled by Mme Lanlaire, helped by the strange valet Joseph. Then she tries the neighbour, ex-officer Mauger. This seems to work. But soon the son of the Lanlaires comes back. He is young, attractive, and does not share his mother's anti-republicans opinions. So Celestine's beauty attracts Captain Mauger, young Georges Lanlaire, and also Joseph. Three men, from three different social classes, with three different conceptions of life. Will Celestine be able to convince Georges of her sincerity ? Will sinister and inflexible Joseph let his views upon Celestine be ruined ? A quite disillusioned depiction of humanity.