A cowboy is arrested for rustling cattle. A lynch mob is formed by his buddy to try and arrange an escape in the confusion. Things go wrong.

Ken Maynard's exceptionally intelligent horse, Tarzan the Wonder Horse, is the star of this western about evil cowboy Steve Frazer (Welch) who gathers horses for slaughter, whose meat is sold to pet food manufacturers. The wild horse Tarzan frees the doomed horses from their corrals, and Frazer convinces the Sheriff that Tarzan is a threat and can be shot on sight. Local cowboy Ken Benson (Maynard) and rancher Pat Riley (Kennedy) work together to clear Tarzan's good name and put Frazier behind bars for his evil deeds.

When a band of American Indians breaks a treaty with the federal government, U.S. Marshals Ken Maynard and Hoot Gibson hit the trail with captured outlaw Duke Dillon (Jack La Rue) to find out what sparked the uprising. They discover clues that point to corrupt Indian agent John Hampton (Kenneth Harlan), but meanwhile, the bandit Dillon pulls a fast one on the marshals, and soon everybody's getting ready for a showdown.

Set in the old west, the stooges are spies for US Calvary; "Buffalo Bilious", "Wild Bill Hiccup" and "Just Plain Bill". Sent by General "Muster" to catch a gang of cattle rustlers, they wind up in a saloon where the boss of the gang hangs out. The boys disguise themselves as gamblers and get into a card game with the villain, but must flee when their identities are discovered. They hole up in a cabin, fighting off the bad guys, until the calvary arrives.