A dying Marshal gives his identification papers to Tom. After Tom arrives in town, the papers drop and are found during a fight so Tom decides to assume the Marshal's identity. Mason, the chief, now sends Rattler, the killer of the Marshal, to also kill Tom. But when he overhears Tom is a fake, they change their plans and now go to arrest Tom for the murder of the Marshal.
Cattle are being routinely stolen from a local ranch, and suspicion centers on a local mountain family. But the Three Mesquiteers are wise to the criminals' deeds. But when a ranger is shot and Stony is framed for the crime, it's up to Lullaby and Tucson to prove his innocence.
Heading west, Ken and Bouncer end up at the Brooks ranch where Ken is to ride Tarzan in the big race. But both the Sheriff and Edmonds are after him and he must hide both himself and the horse until race time.
Cowboy is hired by an archaeologist to help find "Hidden Valley", where an Indian gold treasure is supposed to be buried. Just when he finds it, the archaeologist is killed, and the cowboy his charged with his murder.
Kincade and Blake cause a mail plane carrying a payroll to make a forced landing in the desert. When they try to get the money, prospectors Ted and Si drive them away. With the pilot shot, Ted takes over as pilot figuring another attempt will be made and this time the Sheriff will be there.
Ben Hall offers $1000 for the wild Devil Horse which Jim Wright and Skeeter capture. While Jim is away, Gil Davis kills Skeeter and takes the horse. The Sheriff then arrests Jim for Skeeter's murder. But unknown to them, an outlaw witnessed the killing
Roy visits his home town while on a personal appearance tour. While there he enters a pony express race. To keep him from winning, bad guys try to sabatoge Roy's entry. They fail, or course. Songs include the title song and "Smile for me, Senorita."
Lambert owns the trucking line that ships cattle to market. When he raises his rates Roy decides to ship the cattle on the River Boat. When Lambert and his men are unable to stop the boat, they rustle the cattle.
James Craig is torn between his criminal career as the masked bandit named the "El Paso Kid," and the life of a law-abiding citizen with his long-suffering wife Zoe. He repeatedly tells Zoe, "just one more time," but he is unable to stop which angers her greatly. However, he does have brief moments of heroics such as when he helps the Widow Weeks save her farm.
In this drama, a Mexican woman attempts to live a peaceful life in California. Unfortunately, land-grabbers kill her father and begin harassing her. Desperate, she sends an impassioned plea for help to Washington, who sends her is special aide to mediate.