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.

Nora Dakon, bored with the dullness of her life in a small New Jersey town, leaves her husband and small daughter to run off with Larry Brundage, a wealthy New York City sportsman. Nora's husband kills himself, and, to avoid scandal, Brundage walks out on Nora. She returns to her child and later she becomes a noted singer. Nora moves to Paris, France, and at a party to celebrate the Armistice, she again meets Brundage, who falls madly in love with her daughter, Ruth. To break up their engagement, Nora is forced to tell Ruth of her tragic relationship with Brundage years earlier. Ruth leaves Brundage and soon finds consolation in the love of Tom Cautley, a young art student.

When Buffalo Bill Cody learns that the Union Pacific railroad is making its way through Kansas, he and other heroes of the Wild West join forces to build a town along the route.

Stephen Ghent, a mineowner, falls in love with Ruth Jordan, an arrogant girl from the East, unaware that she is the daughter of his dead partner. Ruth is vacationing in Arizona and Mexico with a fast set of friends, including her fiancé, Edgar. Manuella, a Spanish halfbreed hopelessly in love with Ghent, causes Ruth to return to her fiancé when she insinuates that Ghent belongs to her. Ghent follows Ruth, kidnaps her, and takes her into the wilderness to endure hardship. There she discovers that she loves Ghent, and she discards Edgar in favor of him.

Clint Belmet is a bit of a firebrand and is sentenced to at least 30 days in jail, but his partners, Bill Jackson and Jim Bridger talk a sympathetic Frenchwoman named Felice into telling the bumbling, drunken marshal that Clint had married her the previous night. Clint is released so he can accompany Felice on the wagon train heading west to California.