Ole Gunderstrom has been shot. The circumstantial evidence points to Buck Mason as the murder. Buck and Ole had an argument over a fence between their property. Since Buck the deputy sheriff disappeared right after the murder everyone thinks that he is guilty.
Buck knows he is innocent and has opted to go undercover. Adopting the persona of Bruce Marvel a wealthy eastern tenderfoot he checks into the TF dude ranch. The owner Cory Blaine is running a cattle rustling. Buck acts the perfect clueless easterner but there are instances that betray his knowledge of the west. Skillful detective work results in the capture of the real murderer.
This is a interesting book that has well thought out characters and consistent action. Burroughs lived and worked on ranches in Idaho and Arizona so there is a feeling of authenticity in the stories. It is set in modern times i.e. 1940 but has the feel of a western. One of four westerns that he wrote and this one is my favorite.