On the Circle J ranch, Gene Autry serves as the steady ranch foreman, and his loyal sidekick, Smiley Burnette, brings humor to the duo as Frog Millhouse. Tension runs high as a new owner named Van Fleet is expected to arrive, while rumors swirl about outlaws scouring the property for a helium gas floe that could be sold to foreign powers for use in dirigibles—airships banned by the United States government. After one of the ranch hands is attacked, Gene and Frog set out to track the criminals, pursuing clues to an abandoned house along the trail.
There, they confront Dad Haskell, [Frank Darien], who explains that his daughter Betty [Jean Rouverol] believes he is the owner of the Circle J and is due to arrive from the East. To keep the pretense going, Gene agrees to help maintain the charade and even turns the Circle J into a temporary dude ranch until the real owner lands on the scene. When Betty arrives with her fiancé Walter Gregory [George Walcott] and his mother [Margaret Armstrong], Gene stages a dramatic rescue of Betty from Frog, who poses as an Indian. She is furious once she learns it was all a gag, and that truth stings even more when Betty confesses that Mrs. Gregory had allowed her to charge about $1,500 worth of clothing to her account, a debt she must repay soon.
The next day, while continuing the chase of the outlaw band, Gene shadowing Betty on a ride leads them to a startling discovery—the source of the helium on the property. The pursuing outlaws, aware of the same information, close in on the location. One of the gang even tries to buy the ranch from Dad, who still pretends to be the owner, arousing suspicion in Walter and his mother. Mrs. Gregory then attempts to retrieve the money directly from Dad, who ends up writing a bad check to settle the debt, hoping he can win the money back from her at cards.
Meanwhile, Gene grows suspicious of Randolph Kimball [Ben Hewlett], the chemist who previously told the former owner that the gas on the property was worthless. When Van Fleet finally arrives at the ranch, he is captured and tied up by Frog and [Joe Frisco], who want to keep him out of the way. Unaware of their plan, Gene frees him after encountering the furious owner. Doc Trimble [Harry Holman] wins enough money at cards to cover Dad’s bad check, and Van Fleet arrives to stake his claim, briefly throwing everyone off the ranch—including Walter and his mother—before the dust settles.
In a clever turn, Gene watches Frog blowing up balloons and hatches a plan to use helium by filling an aeronautical balloon, sending Frog aloft in a basket. From the sky, Frog spots the pipeline to the outlaws’ cave, and Gene punctures the balloon with a bullet, propelling the chase toward the cave. A tense shootout follows, with Gene capturing most of the outlaws and arresting Kimball as he tries to flee in a truck. Impressed by Gene’s quick thinking and leadership, Van Fleet offers him the position of ranch manager, and Betty decides that Gene would make a far better husband than her former fiancé.
