Mallett was born in Roaring Spring, Pennsylvania, on March 30, 1945, and grew up in The Bronx in New York City. When he was 10 years old, his father died at age 33 of a heart attack in 1955, which made him depressed and devastated. About one year later, at age 11, Mallett found a Classics Illustrated comic book version of H.G. Wells ' The Time Machine ' in 1956'. Inspired by this literature, he resolved to travel back in time to save his father. This idea became a lifelong obsession and the basis of his research into time travel. Mallett served in the United States Air Force for four years, during the Vietnam War. He returned to civilian life in 1966. This was the year that the science fiction TV series Star Trek started, in which he "quickly became immersed". During its first season, Mallett watched the episode The City on the Edge of Forever that "involved both the theme of time travel and lost love", and this became his favorite of the entire series.