After the Civil War, rancher Thomas Dunson (James Arness) leads a dangerous cattle drive across Texas with a team that includes his adopted son, Matthew (Bruce Boxleitner), and black cowboy Jack Byrd (Stan Shaw), whose presence annoys some of the white cowboys. Fearful of Indians and struggling through the dry terrain, Dunson's men grow increasingly unhappy with his authoritarian ways. Fed up, rebellious Matthew goes to work for another ranch, infuriating his father.