A cavalry deserter poses as a major and leads a wagon train with a hidden cargo of repeating rifles.

Jimmy Wakely befriends Hank Carrdigan, a former outlaw who has served his sentence and wants to go straight. Jimmy, after clearing Hank of a wrongful shooting charge, helps him get a job as an express messenger. Hank drives off some bandits in an attempted hold-up, but recognizes his son Tom as one of the bandits. A later robbery is blamed on Hank but Jimmy and his sidekick Cannonball Taylor bring in the real culprits and clear Hank's name.

Outlaws attempting to kidnap Steve Blaine from a stagecoach are ran off by the sharpshooting of his sister, Sally and rescuers Jimmy Wakely and Cannonball Taylor. Steve is investigating his father's sudden death after charges of theft from the Sloan/Carson mine. Sloan is killed after Wakely learns that ore is being smuggled across the Mexican border into the mine, and then sold at the higher U.S. prices

Jimmy Wakely and Dusty, traveling with the medicine show owned by "Lasses" White, stop at the Ferguson ranch and find the rancher and his wife killed. They take the Ferguson baby to their camp, where outlaws Joe, Slick and Pete attempt to kidnap the baby, while Dusty is reporting the murders to Sheriff Beasley and town mayor Melinda Pringle. Wakely and his singers hide the baby from its legal guardian, Doc Judd Thomas, as they suspect him of being connected with the Ferguson murders.

Doris Rogers, half owner of a dude ranch, as Jimmy Wakely, "Lasses" White and Dusty Smith to help run it. U.S. Marshal Tom Logan, posing as a stage driver, is killed during a mock holdup of new arrivals to the ranch. Brenda Amers and Horatio Pennypacker, eastern jewel thieves, bring their loot to Roy Williams, who owns the other half of the ranch as a blind for his gang which resells stolen jewels. Vaughn, the desk clerk, re-cuts the jewels in a secret room in the ice house. Fearing he will be caught, Brenda refuses Williams her stolen diamonds and hides them in a bar of soap.

Kate Diamond owns the Roaring Falls Trading Post from where she directs her gang's gun-smuggling to the Indians. After she short-changes smuggler Stacey, his men attempt to steal the hidden guns, and attack her foreman Nebraska, but he is saved by Jimmy and "Cannonball" on their way to file a homestead claim at Canyon City. Jimmy renews a long acquaintance with Sheriff Harris and his daughter Jessica. The sheriff is wounded by half-breed Danny when he finds a rifle hidden in the latter's wagon, but Jimmy captures the outlaw, a go-between for Kate and the Indians.Wounded and in bed, Sheriff Harris ask Jimmy not to tell Jessica that she is only adopted and that Nebraska is really her father, although he believes her to be dead.

Jimmy and his pal Cannonball are hired by a rancher and horse breeder to capture Midnight, a wild stallion that has been interfering with local herds and has a reputation as a killer.

Curly Blake, nephew and heir of wealthy Red Rock rancher Jed Gordon, persuades his uncle not to invest in a crooked land scheme promoted by former judge Harmon Steele and his secretary Lem Martin.

Jimmy Wakely wishes to sell to the government a group of wild mustangs which he has captured and trained for rancher Matt Blake. The competition is Flora Carter, the owner of a near-by ranch. The army colonel in charge decides to buy the winning horses of a cross-country race. Flora has her henchmen, led by Sam Phelps resort to foul means in order to try to win the race.

Jimmy joins Cannonball on a visit to the widow Fennamore, Cannonball's old girlfriend, at Firehole. Engineer Colton is killed by henchman Smoky Morgan and Philip Judson hides the body. The engineer, at the request of the widow's niece, Martha, had come to inspect a polluted reservoir. Land Company head Turner and Judson contaminated the water to get the ranchers to vacate so they can grab the land. Judson hires Easy to pose as the engineer, and he reports the reservoir useless but Jimmy's test proves the waters are not deeply polluted. Judson kills Easy to keep him from talking, and casts the blame on Cannonball. But Jimmy has a trick up his sleeve, right after the next song.