Red Butte saloon owner Duke Catlett (Lane Chandler) is the secret owner of a large sheep flock which he grazes on surrounding cattlelands. A range war looks between the cattlemen, led by Bart Mason (Zon Murray), and the sheepherders. Karen Kemp (Barbara Pepper) and her younger brother Rocky (Elvin Eric Field), a young city tough, enroute from Chicago to buy a half interest in a Catlett enterprise are held up by two of the latter's gunmen and lose $30,000. But the Durango Kid (Charles Starrett) gives chase and retrieves the money. At the relay station, Karen meets the Durango Kid again, and his pal Smiley (Smiley Burnette), but does not recognize the former in his guise of Steve Haverly. Durango learns of cattlemen scattering poisoned wheat, but does not know who the instigators are. Smiley's trading post is wrecked and Karen offers Smiley and his boys (Ozie Waters and His Colorado Rangers)a job playing for a show that night. Catlett catches Karen eavesdropping while he and his men are plotting to steal Steve's cattle herd. Catlett realizes he must change his plans and instead of attacking Steve's herd on the south range, he intends to attack the north range, and has Steve informed of the south range attack.