Kleptomaniac Dorothy Lyons is paroled from prison into the custody of her sister June, secretary to "reform" politician Frank Jansen. Ben Grace, associate of crime boss Sol "Solly" Caspar, sees this as a way to smear Jansen's campaign. Seductive Dorothy will do anything to get what she wants, which includes having a good time with Ben-- whom June is now in love with.

Passing herself off as a countess, glamorous Lucy Stavrin hobnobs with the rich and famous along the French Riviera. Aware that Lucy is a phony, jewel-thief Malatroff blackmails Lucy into helping him steal the valuable necklace owned by the young wife of phlegmatic American businessman Sylvester Corbett.