Late on i lonely night made of life's cynical twists, a prosecutor from Chambéry named François Marcorelle meets a Polish girl in a Turkish restaurant in town and follows her up to her room. There, a series of bizarre events lead him to kill a man. Or so he thinks. His friend Georges, a doctor, is convinced this is only one of François' chronic nightmares, a product of Marcorelle's feelings of guilt exploited by his adversaries at the court house. But, this time, Marcorelle is sure, it's all too real. There, lurking in darkness of a movie theater one afternoon, is the proof. But, where does imagination end and reality begin?