

Though Sam would leap into a variety of different hosts, and he would appear to all other people (including Al, at first) as whoever his new host was, he would appear to the audience as Scott Bakula. Many of the episodes recognizably played off the premises of popular movies, but went in a different direction. Also a cheap format, since it made extensive use of existing period wardrobes, locations, and sets, all but eliminating the need to build or make anything for the show, save for the very rare view of Project Quantum Leap itself. If you didn't like one episode, chances are the next would be completely different. The format allowed for an entirely new supporting cast and premise every week. In other words, he Suddenly Always Knew That. At least once a season, Sam would suddenly be revealed to have completely forgotten about his musical career/doctorate in the specialty needed for the leap, etc. The show also established that leaping affected Sam's memory and his own past, allowing the writers to regularly Retcon his skills and personal history (referred to in show as "the Swiss Cheese Effect"). The show's explanation for the time travel was basically a Hand Wave the experiment started Sam's leaps, but afterwards they were controlled by the Powers That Be. Reluctant at the role thrust upon him, Sam assumes the role of the Drifter, assisted as noted by Dean Stockwell's Al Calavicci.

The only way for him to move on from any time period he lands in is to change the lives of people there for the better.

Sam Beckett ( Scott Bakula), caught in a malfunctioning Time Travel experiment that bounces him back and forth into the roles of different people in the past. Quantum Leap (1989-1993) is a NBC Cult Classic series.
