This entry in Republic's "Three Mesquiteer" series, that skipped back forth in time much like Brick Bradford in his "Time Top" machine, finds the Mesquiteers, Stony Brooke, Rusty Joslin and Rico, intervening when an 1870's wagon train of settlers, headed by Dr. Bailey, is attacked by Indians. The wagon train leader is killed and the Mesquiteers agree to guide the settlers to their destination. Bailey and his daughter Anna and the other settlers have been lured westward by offers of cheap land. Arriving, they find that the land sold them by Judge Platt and Sheriff Gorman is practically worthless, but through hard labor and courage they manage to clear it and have reached the point where they are about to make a fair living when they are beset by exorbitant taxes. Judge Platt and his cronies have information that a railroad is to be run through the territory, and they plan to break the settlers by high taxes, regain the land at forced sales, and sell it to the railroad. The Mesquiteers arrange for a cattle sale in order to pay the taxes but Platt and his henchmen, led by Steve Carson, contrive to rob the Mesquiteers as they return from Omaha, and make it appear that the Mesquiteers took the funds and made up the hold-up story. But Stony, in the guise of the Masked Rider (a plot device much favored in the Mesquiteer films with Livingston following his essay of the title role in "The Lone Ranger Rides Again" serial), and his two friends begin a campaign to end the activities of Platt and his gang.