In need of minor repair, the mail plane makes a forced landing at the X Bar X ranch. Roy and Teddy become friends with the aviator, Hank Dempsey, who offers them a joyride to Centralia, where the airport is located. The boys eagerly accept, having to go to Centralia anyway on business for their father. There they meet Larry Cobb, a fine rider who is ill and in need of a stay in the country to regain his health. At the boys' invitation, he comes to the X Bar X for a long visit. In a subplot, he and the boys become involved in aiding an Italian expatriate who has bought a neighboring ranch; in his naiveté, he has hired shady ranch hands who intend to rob him blind and take over the ranch. Finally, when Hank's plane is lost after a powerful storm near Copperhead Gulch, reputedly swarming with poisonous copperhead snakes, Roy, Teddy, and Larry set out to find their friend.

Writing: 7
Characterization: 7
Plot: 7
Overall score: 7