Thomas Mark Harmon (born September 2, 1951) is an American actor. He is known for playing the lead role of Leroy Jethro Gibbs in NCIS. He also appeared in a wide variety of roles since the early 1970s. After spending the majority of the 1990s as a character actor, he played Secret Service special agent Simon Donovan in a four-episode story arc in The West Wing in 2002, receiving an Emmy Award nomination for the role. Harmon's character of NCIS special agent Leroy Jethro Gibbs was introduced in a guest starring role in two episodes of JAG. From 2003 to 2021, Harmon starred in the spinoff NCIS as the same character. Early life Harmon was born in Burbank, California, the youngest of three children. His parents were Heisman Trophy–winning football player and broadcaster Tom Harmon and actress, model, and artist Elyse Knox (née Elsie Lillian Kornbrath). Harmon had two older sisters, the late actress and painter Kristin Nelson, who was divorced from the late singer Rick Nelson, and actress and model Kelly Harmon, formerly married to car magnate John DeLorean. His maternal grandparents were Austrian immigrants. College football After his high school graduation from Harvard-Westlake School in 1970, Harmon completed a two-year associate degree at Pierce College in Los Angeles. After his second season at Pierce, 1971, Harmon received offers from major college football programs, ultimately choosing UCLA over Oklahoma, even though in the previous season, 1971, the Sooners finished second in the nation, while the Bruins had stumbled to a 2–7–1 record, placing last in the Pac-8. After transferring to the University of California, Los Angeles, he started at quarterback for the 1972 and 1973 Bruins. During his first game, his UCLA team produced a stunning upset of the two-time defending national champion Nebraska Cornhuskers. The Bruins were an eighteen-point home underdog to the top-ranked Huskers but won 20–17 on a late field goal by Efren Herrera under the lights of L.A. Coliseum. In his senior year, Harmon received the National Football Foundation Award for All-Round Excellence. During his two years as quarterback in coach Pepper Rodgers's wishbone offense, UCLA compiled a 17–5 record (). Harmon was UCLA's starting quarterback for two seasons, but he was not picked in the 1974 NFL Draft. Harmon graduated cum laude from UCLA in 1974 with a B.A. in Communications. He was inducted into the inaugural class of the Pierce College Athletic Hall