 Rex Allen (Rex Allen), working for the Bureau of Indian Affairs in Washington, is sent west to investigate a sudden outbreak of sudden uprisings by the Apaches. Rex, his partner Slim Pickens (Slim Pickens) and the Rhythm Riders (Michael Barton, Darol Rice, Bud Dooley and Slim Duncan)are met in Red Creek by John Anchor (Roy Barcroft), head of a construction company who has a government contract to build a spur line. A wagon train of emigrants commanded by Jim Allen (Gil Herman)is attacked by Apache Chief Black Hawk (Leonard Nimoy)and his braves. Rex and his friends arrive in time to prevent a massacre, but too late to save the settler s equipment and possessions. The homesteaders, unaware that Anchor engineered the attack to get cheap labor, accept his offer of jobs. Since his brother Jim is Anchor s partner, Rex is reluctant to suspect Anchor, but when Anchor and his head henchman Mack (Zon Murray) continue to swindle the homesteaders with fake payroll robberies and increasing flagrant exploitation, there is a fight between the two brothers. Later, Jim realizes his mistake, and is killed when he accuses Anchor of inciting the Indians. Mary Peterson (Virginia Hall) warns Rex that Anchor has accused him of killing Jim, and Rex and Slim head for the mountains. They are captured by Black Hawk, who has orders from Anchor to kill them.