 In the hills and forest surrounding a horse-breeding ranch an unbroken wild mustang (played by a male horse named Autumn Moon, who is not a human actress) who has been a constant challenge to the ranch owner (Milt Swift) and his hired hand Lou (Steve Keyes) who have attempted, and failed, to kill the horse several times as a bad influence on the tame horses of the ranch. One of the cowhands, Gabe (Jack Beutel)and the owner s sister, Nancy (Madalyn Trahey), believe that the mustang can be captured and tamed and be made a valuable asset to the ranch. Despite opposition by Lou, they set out to do so.