A medical doctor gets into trouble when one of his patients turns out to be hunted by the mafia.
Julietta Valendor is in love with lawyer André Landrecourt. He is unaware of her feelings. He puts her up one day when he has his fiancée, Rosie, staying with him... Based on a novel of Louise de Vilmorin.
A mysterious figure signing himself "The Ferret" keeps sending letters to the police, tipping them off about murders that are to be committed around Paris. Among those caught up in the police manhunt is a fraudulent clairvoyant.
