Cheyenne Jones comes to the Blue River Ranch and asks for a job as a cowpuncher. Actually, Jones's real name is Buck McCloud and he's the new owner of the spread, having inherited it when his uncle died a year earlier. He's roaming the range incognito while trying to identify who's behind the cattle rustling that is afflicting his new business.
Indecisive heiress Dee Dee Dillwood is pushed into marrying her sixth fiancée, but unable to face the wedding night, she flees into the adjacent hotel room of commercial pilot Marvin Payne, who just wants to sleep. She then persuades him to take her to California.
Western star Charles Starrett was amazing; he kept making the same film over and over, but always made it seem as if it was for the first time. In West of Sonora, Starrett once again plays a frontier good-guy named Steve (Steve Rollins, to be exact), who, when the need arises, disguises himself as The Durango Kid, masked righter of wrongs. This time, Steve/Durango champions the cause of 10-year-old Penelope Clinton (Anita Castle), who has spent her short life as the focus of a feud between her grandfathers, suspected outlaw Black Murphy (Steve Darrell) and Sheriff Jack Clinton (George Cheseboro).
Milton Haskins, a math genius known for his infallibility with numbers, quits his job with an insurance company when he discovers he made a mistake, and hooks up with a traveling carnival. His knowledge of mathematics makes him a natural as an assistant at the wheel of fortune. His fiancée begs him to return to his job but he refuses, so she joins the carnival and becomes a striptease artist. When Milton attempts to drag her off the stage, a brawling mêlée breaks out and the entire troupe is arrested by the local police. The carnival is sold but Milton reveals that the new owner has conspired to defraud the insurance company. The insurance company has to accept the carnival in lieu of the money owed, and they allow Milton and his fiancée, Vivian, to stay with and help run the carnival.
