In the bustling, glamorous world of the French Riviera, a popular and talented American nightclub entertainer named Jack Martin finds himself at the center of an unexpected twist of fate. Known for his remarkable impersonations, Jack's life takes a thrilling turn when he is asked to impersonate a wealthy aristocrat, Henri Duran, to whom he bears an uncanny resemblance. The task at hand is not an easy one, as it requires Jack to navigate through high-society functions, deal with Duran's business affairs, and interact closely with the aristocrat's acquaintances, all without revealing his true identity.

The situation grows more complicated when Jack, posing as Duran, finds himself entangled in a web of romantic intrigue. He becomes the object of affection for both Duran's beautiful wife, Lili, and the enchanting nightclub singer, Colette. As Jack struggles to balance his dual identities, he must juggle the affections of these two women while maintaining the charade. The comedy of errors escalates, leading Jack through a series of humorous and challenging situations as he tries to uphold his impersonation of Duran without getting caught, all the while navigating the treacherous waters of love and deception on the Riviera.