A drunken self-destructive woman called Betty wanders through bars and meets a man that drives her to a restaurant outside Paris called Le Trou (The Hole). She meets the middle-aged alcoholic Laure from Lyon, who is the lover of the Le Trou's owner Mario. Laure decides to take care of Betty and brings her to the room next-door in her hotel. Along the days, Betty tells the story of her bourgeois life and her unhappy marriage to Laure and also recalls moments of her promiscuous life.
