Marie (Miou-Miou) is 19 and is bored in her little suburban life with no future. In a café, she meets Gérard (Daniel Duval), a beautiful brown frimeur and voluble, who has no trouble seducing. Blinded by love, too candid, Mary decides to leave her parents and her clerk job to live with the man she considers as the love of her life. But Gerard is a pimp, who soon forces her into prostitution. By "home visit" first, in the street or in the Bois de Boulogne then, the young woman gradually discovers a world of decay and violence.