John Lupton was born on August 22, 1928, in Highland Park, Illinois, to a newspaper writer father. He grew up in Milwaukee, where he was raised and developed an interest in acting after appearing in a couple of high school plays. He began his career with a local stock company and performed in children's theater, eventually training at the American Academy of Dramatic Arts.
Lupton made his Broadway debut in 1949 in a minor part in the Mae West showcase "Diamond Lil". He went on to co-star with Susan Peters in "The Glass Menagerie" and was cast in the Katharine Hepburn 1950 tour of "As You Like It". Hepburn helped introduce him to films and MGM, which led to his becoming a Metro contract player.
As a contract player, Lupton found the going rough, playing bit parts in films such as "Julius Caesar" and "Scandal at Scourie". After two years, the studio declined to pick up his option, and he began to freelance. He appeared in a number of action-oriented yarns, including "Battle Cry", "The Great Locomotive Chase", "Drango", "Taming Sutton's Gal", "Gun Fever", and "The Man in the Net".
Lupton's breakthrough role came in 1956 when he starred in the TV series "Broken Arrow", playing government agent Tom Jeffords. The show was a success, and Lupton's career continued to thrive in the 1960s and 1970s. He appeared in a slew of TV shows, including "Days of Our Lives", "Wagon Train", "Gomer Pyle: USMC", "The F.B.I.", "Ironside", "Kung Fu", "Cannon", "Harry O", "Charlie's Angels", "The Rockford Files", and "B.J. and the Bear".
In addition to his TV work, Lupton appeared in a number of made-for-TV movies and commercials. He was married twice, first to a woman with whom he had a daughter, and then to Dian Friml, the granddaughter of composer Rudolf Friml. Lupton died on November 3, 1993, at the age of 65, and his wife died in 2005.