Quantum Leap (1989): Season 4, Episode 22

4 - 22: A Leap for Lisa - June 25, 1957

Sam leaps into Al Calavicci to prevent the death of his married lover. But when Sam accidentally alters history, and finds out too late about her untimely demise, it could mean the gas chamber for Al and disturbingly a whole new situation at Project Quantum Leap.