Tom Evans is so excited about selling his first herd of cattle that he leaves the herd with his foreman and goes into Yucca City to celebrate. Crooked cattle buyer Ben Crowley hears that Tom is in town and, while he involves Tom in a card game at the saloon, he has his thugs rustle Tom's herd and kill the cowhands. U.S. Marshal Nevada, who has been sent to Yucca City to disable the murderous gang of rustlers and is working undercover as a cattle buyer named Jack McKenzie, sees Crowley cheating Tom at cards. When Tom learns that his cattle have been stolen and his friends killed, he rushes out of the saloon, but Crowley sends a man after him, and the outlaw shoots Tom in the back. Nevada rescues Tom and hides him with the friendly blacksmith, Jeff Lewis, and daughter Mary. Lewis urges Nevada to send for Tom's uncle, Texas marshal Sandy Hopkins, and Sandy soon arrives posing as a dentist. Lewis and Nevada apprise Sandy of the situation, and together they devise a plan to entrap Crowley. Crowley learns that Tom is alive and plots to kill both him and Nevada. Unsuspecting, Nevada meets with Crowley to arrange a deal for the cattle, and is captured and taken to the bandits' hideout. After Crowley's thug Gus fails to kill Tom and is then shot by Sandy, Tom, who has been nursed back to health by Mary, joins up with Sandy to find Nevada. Nevada tricks Steve Carse, Crowley's second-in-command, into releasing him, and subsequently overpowers Steve and engages in a gunfight with the rest of the gang. Sandy and Tom have searched for Nevada all night, and ride to his rescue when they hear the gunfire. Lewis, in the meantime, has detained Crowley in town, but one of Crowley's men escapes from the shootout and warns his boss about the plot. Crowley is about to murder Lewis when Sandy and Nevada arrive and arrest the criminal. With peace restored to Yucca City, Tom reclaims his herd and becomes engaged to Mary, while Sandy and Nevada return home.