Captain Wilks of the Texas Rangers orders Jim Houston and his crew, Thunder Rogers and Jim's brother Bob, to go to Eureka, Texas to break up the Shag Smith gang. After arriving in town, Thunder and Jim accompany the stagecoach to the border, fearing it will be robbed, and Bob is left behind to protect the town. While Jim and Thunder are away, Shag and his gang ride into town. They rob the bank and Bob is shot and killed. When Jim returns he swears vengeance for Bob's death and resigns from the Rangers. He and Thunder pursue Shag into Mexico. In the town of Alemeda, Jim sees beautiful Spanish dancer Tonita at the Clubo Americano. Afraid that she will recognize him as the Ranger who guarded her stagecoach, Jim adopts the name "The Tonto Kid." Dave, a member of Shag's gang, is interested in Tonita, but when he forces his attention on her, Jim steps in and knocks Dave out. His bravery impresses Shag, who asks Jim to join his gang. Jim agrees on the condition that Shag accompany him on a bank robbery in Eureka. Waiting for the gang in Eureka is a group of Rangers assembled by Thunder. During the robbery, all the gang members except Shag are captured. Jim and Thunder once again trail the bandit to the Clubo Americano where Jim finally shoots him. Jim returns to the United States with Tonita.