A sinister aristocrat known as Lord Bluebeard is looking for a beautiful woman to become his wife. Lured by his great riches, many noble families bring their most eligible daughters to meet him, but none of the young women want to marry him, both due to his ghastly appearance and because he has already had seven previous wives - all of whom have mysteriously vanished without a trace. Bluebeard's great wealth, however, persuades one father to give his daughter's hand to him. She has no choice but to marry him, and after a lavish wedding feast she begins her new life in his castle.
One day as Bluebeard is going away on a journey, he entrusts the keys to his castle to her, and warns his wife never to go into a certain room. Caught between the fear of her husband's wrath and her own curiosity, she is unsure of what to do regarding the forbidden chamber. Her curiosity manifests itself in the form of an imp who taunts and mocks her with potential promises that the room might contain, whereas her better judgement comes in the form of a guardian angel, who attempts to dissuade her from entering the locked door.
When her curiosity finally gets the best of her, she realizes that she has placed herself in great danger. She enters the room, Melies at this point builds the suspense by keeping the lighting levels low, making out strange bag shapes. The room is revealed to be a torture chamber and these bags are revealed to be dead bodies; the seven past wives of the murderous Bluebeard hanging on hooks, dripping stale blood on to the floor. The new wife drops the key in her horror, and is stained with dead wives' blood which the wife relentlessly tries to wash off. Later that night she has a dream of seven giant keys haunting her with a sense of Freudian guilt from the dominating presence of Bluebeard. On Bluebeard's arrival he discovers his wife's untamable curiosity and violently shakes her. She runs to the top of the tower, and calls to her sister and brothers. Her relatives save her from death and pin Bluebeard with a sword to the castle walls. The angel appears to restore the murdered wives to life and they are married to seven great lords.