Beautiful young housewife Séverine Serizy cannot reconcile her masochistic fantasies with her everyday life alongside dutiful husband Pierre. When her lovestruck friend Henri mentions a secretive high-class brothel run by Madame Anais, Séverine begins to work there during the day under the name Belle de Jour. But when one of her clients grows possessive, she must try to go back to her normal life.

The story of a father, his 23-year-old daughter who goes back home one day because she has just been dumped, and his new girlfriend, who is also 23 and lives with him.

Pierre and Manon are poor. They make documentaries with nothing and they live by doing odd jobs. Pierre meets a young intern, Elisabeth, and she becomes his mistress. But Pierre will not leave Manon for Elisabeth; he wants to keep both.