 After being discharged from the army for insubordination, Antoine Doinel (Jean-Pierre Léaud) visits his former girlfriend Christine Darbon (Claude Jade), and her father finds a temporary job of night watchman for Antoine in a hotel. The naive Antoine is deceived by a private eye in his first night shift, and fired on the next morning. The investigator invites the clumsy Antoine to work in his company, where he is assigned for some minor jobs, until he has to investigate why the owner of a shoes store, Mr. Georges Tabard (Michel Lonsdale), is detested by his employees. Meanwhile Antoine falls in love for the gorgeous Mrs. Fabienne Tabard (Delphine Seyrig).