Quantum Leap was a science fiction television program which ran from 1989 to 1993 on NBC. It followed the adventures of Dr. more...
Sam Beckett (played by Scott Bakula), a brilliant theoretical scientist who finds himself abruptly and uncontrollably jumping in time, temporarily switching places with diverse people at various times within his own lifetime, the second half of the 20th century: "leaping from life to life, striving to put right what once went wrong, and hoping each time that his next leap will be the leap home".
The show's ninety-seven episodes aired on NBC between March 1989 and May 1993.
Dr. Samuel Beckett is a brilliant theoretical physicist with at least three doctorate degrees. He has theorized that a person may time travel, within the period of his own lifetime. In a highly-classified, US government-funded, research facility somewhere in the Nevada desert, he is proceding with a grand experiment to prove his theory. However, the funding for Project: Quantum Leap is about to be cut. In an effort to prove that his theories are correct, he turns on his device, steps in to the time travel chamber and vanishes.
Sam appears in the past with no memory of who he is or where he is. This side-effect of uneven amnesia, is called Swiss-cheesing or (as a technical term in the show's universe) magnafluxing, which prevents him from remembering most of the details of his own life. His friend from his original time, Al Calivicci (played by Dean Stockwell), appears to him as a holographic projection from the "imaging chamber" — usually only visible and audible to Sam. Al is the project observer and a U.S. Navy admiral. Along with the (possibly) sentient supercomputer named Ziggy, Al is able to help Sam "set right what once went wrong" before he leaps out in to the next person. At the beginning of nearly every episode, as Sam leaps in to the next person, the catch phrase of "Oh boy..." was uttered.
As the episodes proceed, Al, Sam and Ziggy wonder why, in these seemingly random leaps, they are always put in a position to fix something that went wrong. They gradually develop a theory that the experiment has been mysteriously co-opted by an unidentified higher power, which uses him (for unknown reasons) to avert tragedies in ordinary people's lives. This is later confirmed indirectly when Sam meets an "evil leaper" who knows that his job is to set wrong what once went right.
The term holographic projection is taken from the program, although it is not the same as real holography. The show's "hologram" is a three dimensional projection; Al enters an "Imaging Chamber" in which the image of Al and anything he is touching, e.g., a person or cigar, are visible to Sam and Sam can hear Al speak, and correspondingly events in the past are visible and audible to Al. However, throughout the series, it has been found that animals, young children, and the mentally ill can see Al. This has been used to Sam's advantage on a few occasions, such as Al soothing a crying child, leading a dog away from Sam, or speaking directly with an asylum inmate.
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