The story of LTC John Paul Vann (Paxton) and his work as a military and civilian advisor in Vietnam over a ten year period (1962-72) until his death in an accidental helicopter crash. As a military advisor, Vann attempted to fight corruption in the Vietnamese army, recognizing the need to build trust among the Vietnamese peasantry. When his recommendations were ignored by the U.S. military, he exposed falsified battle reports and other deceptions to a New York Times reporter, effectively ending his military career. As the war escalated, however, Vann returned to Vietnam as a civilian advisor under Nixon's "Vietnamization" program, ending as the defacto commander of Vietnamese forces in the successful defense of the Central Highlands during the 1972 Easter Offensive. The film also examines Vann's character flaws, the chief of these being his adulterous nature and affairs with Vietnamese women which resulted in a forced marriage to a Vietnamese schoolgirl whom he had gotten pregnant.