Françoise, a charming young saleswoman for a leading jeweller, is being courted in vain by a billionaire shipowner. He attributes her failure to the existence of a rival, and decides to have her followed by a private detective. Françoise, commissioned by her boss to transport a valuable necklace to Cannes, is accompanied by a bodyguard charged with her safety. Françoise, the bodyguard and the detective meet on the train and a series of misunderstandings ensue.
| Actor | Role |
|---|---|
 Dany RobinFrançoise | Françoise |
 Daniel GélinMichel Corbier | Michel Corbier |
 Jacques JouanneauChatou | Chatou |
 Georges ChamaratLe commissaire | Le commissaire |
 Michel GalabruAristide Oranos | Aristide Oranos |
 Fernand SardouEmile | Emile |
 Noël RoquevertRobillard | Robillard |
 Jean HébeyLe bijoutier | Le bijoutier |
 Robert RollisUn amoureux de Françoise | Un amoureux de Françoise |
| PPierre DannyNot listed | Not listed |