Released from prison after serving 16 years of a quarter-century sentence for murder, reformed gunfighter John Wesley Hardin (Rock Hudson) completes a written autobiography, hoping to convince his son (Race Gentry) not to follow a criminal path. In it, he shows how having left home as a young man against the wishes of his strict preacher father (John McIntire) and his first love (Mary Castle), he is hurled into the outlaw life when he shoots a man in self-defense during a card game in a saloon.