A land grabber frames a rancher who's discovered copper on his land.
Bar Cross Ranch foreman Gene Autry and his pal, Frog Millhouse, spend six weeks in New York City trying to convince Tom Bennett to return to Solitude, Arizona, to run the ranch left to him by his late father. Believing that the West is too dull for him, Tom is reluctant to go home to the ranch, but Gene forcibly puts him on the train. During the ride home, Gene meets up with his old friend, gambler Duke Winston. Upon arriving in Solitude, Tom escapes from Gene's watchful eye and meets singer Taffy and her teenaged sister Patsy, who have come to town to find a job. Believing that Duke is the big shot he made himself out to be, Tom asks him to help Taffy get a singing job in the local saloon. Duke, who has convinced E. G. Blaine, the mine owner who runs the saloon, to hire him as the manager, does hire Taffy. Gene, meanwhile, assumes that Taffy is a common showgirl and is after Tom's money, and his rudeness toward her starts a brawl in the saloon. Soon after, Gene tries to get Tom to settle down to work, but his efforts are interrupted because waste from Blaine's copper mines has been dumped in the local watering holes, poisoning the cattle. Gene asks Blaine to build proper drainage pits to clean the water, but when the foreman states that they would have to shut down operations for two weeks to do so, Blaine refuses. Infuriated by Blaine's greed, Gene goes to Judge Bent to obtain an injunction to stop the mining, but learns that he must travel to Phoenix to get it. While he is at the train station, Gene runs into Patsy and Taffy, to whom he apologizes for his earlier behavior. During Gene's absence, Tom grows frustrated watching the cattle die and, despite Frog's warning that they should wait for the injunction, rounds up the ranchers and attacks the mine. During the ensuing shootout, Tom kills one of Blaine's henchmen in self-defense, but Blaine makes it look like murder. The miners organize into a lynch mob, but Duke returns and persuades Blaine to stop them and use Tom as a bargaining chip. When Gene arrives, Blaine tells him that if the injunction is served, he will make sure that Tom is hanged. Gene agrees to withdraw the injunction if Blaine starts digging a drainage system voluntarily and ensures that Tom will receive a fair trial. Tom and Taffy are mystified by Gene's reluctance to act, however, and believe that he is now in league with Blaine. Soon after, Judge Bent advises Tom that he will be acquitted, and Gene explains why he withheld the injunction. Their friendship restored, Gene and Tom join forces against Blaine, who has refused to stop dumping the waste. While the judge arranges for a change of venue, which will free Tom from Blaine's control, Gene serves Blaine with the injunction. Blaine orders his henchman, Sheriff Simpson, to organize a frame-up that will implicate Gene and Tom in a jailbreak, during which they can both be killed. Duke learns of the plan, and even though he is being watched, he alerts Taffy. Although Taffy cannot warn Gene herself, Patsy is able to ride to the ranch and get Frog and the other men. While Gene and Tom are trapped by Blaine's men in the jail, Duke sneaks in to help them during the shootout. Blaine's men set the building on fire, and Duke is shot and killed as he helps Gene and Tom escape. Frog and the ranch hands stampede a herd of cattle through the town to scatter the mob, and soon the criminals are apprehended. Later, Gene, Taffy and their friends celebrate Tom's twenty-first birthday with a picnic.