Liza Minnelli The Muppet Show : Season 4 Episode 9

The Muppets present a murder mystery. Kermit is a private eye hired by Liza O'Shaugnessy, an actress whose production is being terrorized by a killer. The director, Fritz (Strangepork), is shot. The police assign Patrolbear Fozzie to the case, and he interrogates the cast: "All right, which one of you killed the director?" The suspects are themselves killed one by one, until Kermit and Liza team up to unmask the true killers.