Mack MacKay is a stand-up comedian who gets entangled in a dangerous predicament with a mobster who has designs on his female partner in a comedy act trio that Sam leaps into in the Season 4 episode of Quantum Leap tilted "Stand Up". The part of Mack is played by comedian/actor Bob Saget, known for his role as Danny Tanner on the long-running ABC-TV sitcom Full House.