Groucho Marx, Harpo Marx, Chico Marx, Ilona Massey, Vera-Ellen, Marion Hutton, Raymond Burr, Melville Cooper, Paul Valentine, Bruce Gordon, Marilyn Monroe, Leon Belasco, Eric Blore, Otto Waldis
The Marx Brothers help young Broadway hopefuls when they get mixed up with gangsters due to a tin of sardines containing Romanoff diamonds.