John W. "Jack" Burns [Kirk Douglas] is a roaming ranch hand who travels with his horse Whiskey, carrying no identification and having no fixed home, sleeping wherever night finds him.
One day, as Burns crosses a highway into town, his horse Whiskey is frightened by the traffic. He then visits Jerry Bondi, the wife of old friend Paul Bondi, who has been jailed for aiding illegal immigrants. Burns dislikes a society that imposes limits on a man’s freedom.
To break Bondi out of jail, Burns decides to get himself arrested. After a barroom fight against a one-armed man Bill Raisch, in which he must fight with only one arm, Burns is arrested. When the police release him, he deliberately punches a cop to get put in jail. Bondi is initially pleased to see him, and Burns defends Bondi from Deputy Sheriff Gutierrez George Kennedy. At night, inmates see through one of the jail’s bars using two hacksaw blades that Burns had hidden in one of his boots. Gutierrez summons Burns in the middle of the night and beats him. Burns loses a tooth which he pockets. He cannot get Bondi to escape with him, as Bondi has accepted his two-year sentence; his family means he has too much at stake to risk becoming a fugitive carrying a five-year term.
Burns breaks out by himself, returning to Bondi’s house, where he picks up his horse and some food from [Jerry Bondi]. They talk about what might have been, and he acknowledges he could never love her the way Bondi does; he never wanted to settle down. He asks for a kiss to give him the energy to reach the mountains, and they kiss.
After the jailbreak, the sheriff learns Burns served in the Korean War, including seven months in a disciplinary training center for striking a superior officer. He also received a Purple Heart and a Distinguished Service Cross for valor in battle, which gives the sheriff some sympathy for Burns.
Burns heads for the mountains, intending to cross the border into Mexico. The police mount an extensive search, with Sheriff Morey Johnson and Deputy Harry searching in a jeep. A military helicopter is brought in, as the Air Force asks to give their pilots some practice. The aircrew locate Burns and relay his location to the sheriff. Whiskey is repeatedly spooked by the helicopter, which hovers, so Burns shoots the tail rudder, forcing the pilot to crash land. The pilots are okay, but their general is angry at the cost to the military and voices his complaints over the radio, which the sheriff cuts off.
Deputy Gutierrez is on foot, chasing Burns. He sees the horse on a corner and raises his gun, telling Burns to show himself, but Burns is behind him, and knocks him over. He then throws away Gutierrez’s weapons and leaves the tooth in Gutierrez’s pocket. Burns continues toward the mountains with Whiskey. Surrounded on three sides, he finally crests the Sandia Mountains and escapes into a broad stand of heavy timber, with the lawmen shooting after him. Burns is shot in the ankle, and the sheriff believes he has escaped.
Burns tries to cross Highway 66 in Tijeras Canyon during a heavy rainstorm, but Whiskey is spooked by the lights. A truck driver strikes Burns and Whiskey, throwing them to the roadside. Burns is conscious and Whiskey neighs in distress. The sheriff arrives and, asked by the state police if Burns is the man they’ve been seeking, says he cannot confidently identify him because he has never seen the man up close. Whiskey is put down, and a shocked Burns is taken away in an ambulance.
