...und abends in die Scala

Nobody knows the real identity of famous singer Gloria del Castro because she is married to the secretary of family Pierre de Motestant, who shall not know that she is a star. When she get to know that her husband has an affair, she decides to disclose her identity and sign a contract with the Berliner Scala. But shortly after that peace in the family is restored and she is unwilling to fulfill the contract. This is the chance for Catarina Duval a Parisian vaudeville actress who wants to become a revue star. She is engaged as substitute and presented as Gloria del Castro to the audience. At the premiere night real Cloria del castro is watching the show with her stand-in. How will she react? —Anonymous