Mademoiselle Nicole (Colbert), the daughter of a destitute aristocrat on the French Riviera lands a charming American millionaire (Cooper) only to find he has been married seven times previously. Determined to teach him a lesson about fidelity, Nicole is going to make sure that there will be no number nine. So begins a battle of the sexes as the wily new bride sets out to tame her Bluebeard and he tries his best to play the game his way.