In this comedy drama that spoofs detective pictures from the 1940s, Tucker (Michael Caine) is a private eye hired by Anglich (Michael Constantine), a wealthy man who is trying to find the whereabouts of his long lost daughter. Tucker's sleuthing leads him to Ellen (Natalie Wood) and Mianne (Kitty Winn), two members of the decidedly unusual Prendergast Family. So far as Tucker can tell, either Ellen or Mianne is Anglich's missing child, but he's not quite sure which. The supporting cast includes Timothy Carey, Thayer David, Liam Dunn, and Liz Renay; Humphrey Bogart impersonator Jerry Lacy appears in the opening credits.