When Tasker kills Roy Rogers he takes one of his young sons. Fifteen years later the other son Roy arrives buying a ranch in the valley where Tasker now controls the water supply. Roy organizes the ranchers for a showdown with Tasker not knowing that his brother is Tasker's chief henchman.

When Professor Marsh disappears while searching for the lost city of Lukachukai, his daughter enlists the help of the Three Mesquiteers.

Elmer attempts to elope with his fiancée, but they escape her parents by driving off in a car that's actually owned by a wanted gangster. When they hear on the radio that the police are looking for them, they dump the car and hide out near a farmhouse. But the farmer's radio also broadcasts the couple's description, so they run away and start hitchhiking, only to be picked up by two policemen. They manage to flee into a railroad yard and hop a train that turns out to be refrigerated. Finally they decide to turn themselves in -- just as they learn that the real crooks have been apprehended.

When a small town doctor buries his twin brother, a practitioner of the black arts, he believes him dead; but subsequent events force him to realize that his brother has, in fact, returned from the dead as a vampire and is seeking revenge on the doctor, who had killed him in self-defense.

Sheriff John Higgins quits and goes into prospecting after he thinks he has killed his best friend in shooting it out with robbers. He encounters his dead buddy's sister and helps her run her ranch. Then she finds out about his past.