山姆（山缪的暱称）意外的旅程起源于他的时间旅行实验被某个神秘、无法辨识的高能量体所吸收，这个能量体利用他（原因不明）来避免一些普通人生命中所遭遇到的悲剧发生。山姆也遭受不规则的失忆症所苦，又称为「蜂窝乳酪」（Swiss-cheesing）或是（影集中较为技术性的名词）「磁粉探伤」（magnafluxing），这让他无法记得他自己生命中大部分的细节。他与他自己时空唯一的连结，是他朋友艾尔（Al）的全像投影（通常只有山姆看得见）。艾尔（由迪恩·史多克威尔（Dean Stockwell）饰演）是一位美国海军上将，也是这个时间旅行计画的原创人和主管。
播出日期: 1989-03-26
运行时间: 70 min
概述: September 13, 1956: Sam Beckett wakes up in 1956, disoriented, suffering from amnesia, but he has the awful realization that he does not belong there...
播出日期: 1989-03-26
运行时间: 19 min
概述: September 13, 1956: After Tom Stratton comforts his wife and prevents her from having a premature birth, instead of leaping to save his wife and child. He instead realizes that instead of leaping home, he's lept into Ken Fox, a minor league baseball player in Texas at the end of the 1968 season, in the middle of a game, where he must make the winning play in order to leap further. Ken Fox makes a home-run, and Sam leaps into Dr. Gerald Bryant as a school teacher in the middle of a class.
播出日期: 1989-03-31
运行时间: 45 min
概述: June 15, 1972: Sam leaps into the persona of a womanizing college professor in 1972, encounters his lost love and attempts to reshape the past
播出日期: 1989-04-07
运行时间: 46 min
概述: October 24, 1974: Sam lands in 1974 as a young boxer caught between fight-fixing gangsters and hopeful nuns who now own his contract.
播出日期: 1989-04-14
运行时间: 45 min
概述: August 5, 1956: Sam finds himself on a Texas ranch in 1956 as a submissive veterinarian in love with a tough rancher.
播出日期: 1989-04-21
运行时间: 45 min
概述: November 8, 1965: Sam becomes a hit man in 1965 whose romance with the godfather's girlfriend places him in danger.
播出日期: 1989-05-03
运行时间: 45 min
概述: August 8, 1955: Sam experiences racism firsthand when he leaps into the body of an elderly black man in the pre-civil rights South of 1955.
播出日期: 1989-05-10
运行时间: 45 min
概述: June 6, 1961: Sam leaps into the life of a teen-age hot-rodder who must stop his sister from marrying a wealthy bully.
播出日期: 1989-05-17
运行时间: 45 min
概述: April 14, 1953: With looks that could double for Humphrey Bogart, Sam is Nick Allen, a private investigator looking for the murderer of his partner and, if he doesn't find the answer in time, himself. The case is solved with a number of Casablanca references as Sam launches a new pulp novelist along the way.
