In a dystopian future, the city of Los Angeles in the year 2247 is governed by a high-tech society. Jack Deth, a hard-boiled police trooper, is tasked with bringing down Martin Whistler, a malevolent psychic criminal. Whistler has the ability to turn people into zombie-like creatures known as "Trancers" with the help of his mind-controlling powers. Having eluded capture in 2247, Whistler manages to escape through time by transferring his consciousness back to 1980s LA. His nefarious scheme involves targeting the ancestors of the future governing council, aiming to alter the course of history by killing them before they can rise to power.

To stop Whistler's plan, Jack is sent back to the 1980s via a drug-induced time travel process, which allows him to inhabit the body of one of his own ancestors, a journalist named Phil Dethton. Upon arriving, Jack adapts to the cultural shock and begins his search for Whistler. He teams up with Leena, a spirited punk rock girl, who becomes an unwitting ally in his mission. As Jack traces Whistler's steps, he struggles to not only prevent the alteration of the future but also to navigate the complexities of a bygone era, all while the time on his temporal stay in the past is running out.