The plot revolves around billionaire Jean-Marc Clément (Yves Montand) who learns that he is to be satirized in an off-Broadway revue. After going to the theatre, he sees Amanda Dell (Marilyn Monroe) rehearsing the Cole Porter song "My Heart Belongs to Daddy", and, by accident, the director thinks him an actor suitable to play himself in the revue. Clément takes the part in order to see more of Amanda and plays along with the mistaken identity, going by the name Alexander Dumas.