Quantum Leap is an American television series that was broadcast on NBC

NBC

The National Broadcasting Company is an American commercial broadcasting television network and former radio network headquartered in the GE Building in New York City's Rockefeller Center with additional major offices near Los Angeles and in Chicago...

 from March 26, 1989 to May 5, 1993, for a total of five seasons. The series was created by Donald Bellisario

Donald Bellisario

Donald Paul Bellisario is an American television producer and screenwriter who created and sometimes wrote episodes for the TV series Magnum, P.I., Airwolf, Quantum Leap, JAG, and NCIS...

, and starred Scott Bakula

Scott Bakula

Scott Stewart Bakula is an American actor, known for his role as Sam Beckett in the television series Quantum Leap, for which he won the Golden Globe Award for Best Actor – Television Series Drama in 1991 and was nominated for four Emmy Awards. He also had a prominent role as Captain Jonathan...

 as Dr. Sam Beckett, a physicist from the (then future) year of 1997, who becomes lost in time following a time travel experiment, temporarily taking the places of other people to "put right what once went wrong". Dean Stockwell

Dean Stockwell

Dean Stockwell is an American actor of film and television, with a career spanning over 65 years. As a child actor under contract to MGM he first came to the public's attention in films such as Anchors Aweigh and The Green Years; as a young adult he played a lead role in the 1957 Broadway and...

 co-starred as Al Calavicci

Al Calavicci

Rear Admiral Upper Half Albert “Al” Calavicci USN is a fictional character on the science fiction drama Quantum Leap, created by Donald P. Bellisario and played by Dean Stockwell.-Biography:...

, Sam's womanizing, cigar-smoking sidekick and best friend, who appeared as a hologram that only Sam, animals, and young children could see and hear.