The film is set in the 1950s in a large country residence as a family and its servants are preparing for
Christmas. When the master of the house is discovered dead in his bed with a dagger in his back, it is presumed that the murderer must be one of the eight women in the house. Over the course of the investigation, each woman has a tale to tell and secrets to hide. The film opens with Suzon returning from school for Christmas break, finding her mother Gaby, her younger sister Catherine, and her
wheelchair-using grandmother Mamy in the living room, where most of the action of the film takes place. Their conversation drifts to the subject of the patriarch of the family, Marcel, and Catherine leads the first song of the film, "
Papa t'es plus dans le coup" (). The singing wakes up Suzon and Catherine's aunt Augustine, who initiates arguments with the rest of the family and the two servants (Madame Chanel and Louise), eventually returning upstairs and threatening to commit
suicide. Mamy jumps out of her wheelchair trying to stop her, haphazardly explaining her ability to walk as a "Christmas miracle." Augustine is eventually calmed down, and she sings her song of longing, "
Message personnel" (). The maid takes a tray upstairs, finds Marcel's stabbed body, and screams. Catherine goes up to see what has happened and locks the door. The others finally go up to Marcel's room to see him stabbed in the back. Catherine tells the others that they should not disturb the room until the police arrive, so they re-lock the door. Realizing that the dogs did not bark the night before the incident, it becomes clear that the murderer was known to the dogs and therefore must be one of the women in the house. Attempting to call the authorities, they find that the telephone line has been cut, so they will have to go in person to the police station. Before they can do so, the women are distracted by the announcement that someone is roaming the garden, someone whom the guard dogs are not chasing. The person turns out to be Marcel's sister Pierrette, a
nightclub singer who is also rumored to be a prostitute, and who has not been allowed into the house before due to Gaby's dislike for her. When questioned, she claims that she received a mysterious telephone call in which she was informed that her brother was dead. She sings "A quoi sert de vivre libre" (), commenting on her sexual freedom. It is realized that she has been to the house before, as the dogs did not bark and she knew immediately which room belonged to her brother, making her the eighth potential killer. The women try to start the car, and find that it has been sabotaged, cutting them off from help until the storm subsides and they can hitchhike to town. The women spend their time trying to identify the murderer amongst them. It is learned that Suzon returned the night before to tell her father in secret that she was
pregnant. She sings a song to Catherine, "
Mon amour, mon ami" (), about her lover; however, she was sexually abused by her father. We later learn that Suzon is not Marcel's child but is the child of Gaby's first great love who was killed not long after the child was conceived; every time Gaby looks at Suzon, she is reminded of her love for him. Suspicion then swings to Madame Chanel, the housekeeper, whose actions the night before seem suspicious. It is revealed that she had been having an affair with Pierrette, who went to see her brother that night to ask for money to pay off her debts. When some members of the family react in outrage to the fact that she is a
lesbian, Madame Chanel retreats to the kitchen, and sings "" (So as to Not Live Alone). In the meantime, we find out that Mamy, Suzon and Catherine's "old and sick" grandmother, not only can walk but also possesses some valuable stock shares that could have saved Marcel from his bankruptcy. Out of greed, she lied that her shares had been stolen by someone who knew where she was hiding them. Gaby also tells Augustine that Mamy killed their father, which leads to Augustine threatening to kill Mamy, and the two sisters consequently locking her in a cupboard. The spotlight moves to Louise, the new maid, who is found out to be Marcel's mistress. She declares affection for Gaby, but also expresses disappointment in her for her weakness and indecision. She is questioned by Augustine (who is revealed to be a virgin) on how to seduce a man. She then sings "
Pile ou face" (, but referring to the ups and downs of life), to an entranced Augustine and removes the symbols of her servitude, her maid's cap and apron, asserting herself as an equal to the other women. Gaby sings "Toi Jamais" (), about Marcel, saying that he never paid enough attention to her, while other men did. It is revealed that she had an affair with Marcel's business partner, Jacques Farneaux, the same man who has been having an affair with Pierrette. The two women get into a fight that turns into a passionate make-out session on the living room floor, a scene which the others walk in on and are stunned by. Eventually, Madame Chanel discovers the solution to the mystery, but she is silenced by a gunshot. While not struck by the bullet, she becomes mute out of shock. Catherine takes the lead, revealing that she hid in her father's closet from where she saw all the other women talk to Marcel the night before. She explains the mystery: Marcel faked his own death, with her help, to see what was really going on in his house. She says that he is now free of the other women's clutches and rushes to his bedroom only to witness Marcel shoot himself in the head. Mamy closes the film with the song "
Il n'y a pas d'amour heureux" () as the women clasp hands and face the audience. ==Cast==