Roy Rogers, a Nevada State Ranger Captain in charge of the Rangers Reclamation Service, makes a trip to Las Vegas for the annual Heldorado Frontier Days Festival, as he wants to help his old friend Gabby Whittaker who originated the idea (at least, in this film).In Las Vegas, Roy meets heiress Carol Randall, who has been selected as the Queen of the Heldorado. Roy is informed that the F.B.I. wants an immediate investigation of the counterfeit thousand dollar bills that are being passed over the gambling tables at the casino.

On vacation at his ranch, western actor Roy quickly finds himself involved with a horse rustling operation and a boy ward of one of the rustlers, leading to the kidnapping of Roy's trick horse Trigger by the gang with a demand for ransom.

The life of the legendary Texas cowboy with his horse, Widowmaker, and how his romance with Slue Foot Sue disrupted it.