Young boxer Jack Ranney agrees to challenge ' Young Kilroy ' and knocks him out with his first punch. When he is told Kilroy is dead, Jack hurriedly heads West and finds a job on a ranch, boasting to all the fellows that he is a killer, unimpressed, they call him a greenhorn. Meanwhile, Jack's sweetheart Mary, learns Kilroy is alive and she heads West to tell Jack the news, arriving just in time to see him single-handedly save the ranch from a raid by the notorious Lopez Cabrillo and his entire gang.