On August 21, 1933, Violette Nozière, 18, poisoned her parents with sleeping pills, before going out to dance. When she returns, she makes sure they are inanimate before opening the gas to make it look like a suicide, then calls for help. Her father did die, but her mother survived. After the survivor's testimony, Violette, already suspicious in the eyes of the investigators, is arrested. The young woman accuses her father of having abused her, but it is the financial motive that justice retains. The case will fascinate public opinion and intellectuals of the time.