"Mistress" is a comedy drama starring Ralph, Robert De Niro, Danny Aiello, Eli Wallach, and more. The film follows Marvin Landisman (Robert Wuhl), a struggling Hollywood screenwriter who catches a break when a producer offers to help find investors for his screenplay. In exchange for their financial support, all three investors insist their mistresses — Beverly (Ralph), Patricia (Jean Smart), and Peggy (Tuesday Knight) — get roles in the film, ultimately resulting in drastic changes to the screenplay that upset Marvin's vision.