In the late 1930s two American sisters, Laura and Kate Barlow, travel to France where they perform séances at cabarets with Laura hosting the session and Kate channeling the spirits. A public performance of theirs is witnessed by French film producer Andre Korben, who books them for a private session and is moved by the spirit that visits him.

Feeling stifled by the lack of innovation in the French film industry, Korben convinces investors and his team to film a séance as it happens. Unfortunately for Korben the reels look ridiculous, though the director is drawn to Laura who, despite not being a spiritualist, has a face that photographs well. The film team conceives of a more conventional script in which Laura will play a medium who channels the spirit of a widower's wife and the three become locked in a love triangle with the widower unsure if he is falling in love with his former wife or the medium. Read more on Wikipedia.