Crooked politician Gus Sloan (George Eldridge) , along with dry-goods store owner John Rogers (Henry Roquemore) and their henchmen are trying to grab up all the ranches in San Joaquin valley and blame their deeds on the A&M Railraod Company. After Sloan has acquired all the property, he plans to sell it at a high profit to an eastern syndicate for railroad right-of-way. Cattleman Jim Blake (Joseph Bernard), opposing Sloan, is murdered by crooked deputy Tanner (Carl Sepulveda), on Sloan's orders. Gil Blake (Tex Ritter), the murdered man's son, exacts revenge as he and his cowhands, Jimmy (Jimmy Wakely, Johnny (Johnnny Bond) and Scotty (Scotty Harrell), become fugitives by doing their best to help the lone rancher hold-out, Boduine Carter (Henry Hall) and his daughter Jane (Jennifer Holt). Enter "Rocky" Morgan, actually the son of the railroad owner, working undercover, and aids Gil and the Carters in there fight as the mysterious Black Rider. However, in doing so, to gain Sloan's trust in order to trap him, he alienates the people he has been sent to help.