 Bronco-bustin  Tim Torrant(Tim McCoy)breaks "killer", the wild horse, and wins the admiration of the town and a job with the Rafter-O outfit, riding the range to track down the horse thiefs who have been menacing the area. Ranch foreman Dick Stark(Wallace MacDonald), who considers himself engaged to Patsy Olcott(Shirley Grey), the daughter of ranch owner Hiram Olcott(Lafe MeKee), becomes jealous of Tim.Stark, after getting the short end of a fist and gun fight with Tim, quits his job. Tim discovers two rustlers trying to work a Rafter-O brand in a Box-R brand,that of neighboring rancher Walt Corson(Montague Love). Further investigation revelas that Corson s horses have been stolen also, and the guilty party was trying to start a war between the two ranchers. Tim suspects rancher Hatch Engall(Wheeker Oakman)but has no proof. It is through Stark, who has joined the rustlers for the purpose of catching them and getting himself in right with Patsy and Mr. Olcott, that Tim gets the information that leads to the capture of Engalland his gang---and the rescue of Patsy, who was being held for ransom by Engall.