 At the outbreak of the War of Secession(the Civil War as called in this film, and still called in some parts of the South)U.S.President Abraham Lincoln(Joe Mills)dispatches ex-Pony Express rider "Kentucky" Carson(Tom Tyler)to oversee an area of the frontier left unprotected by the withdrawal of Army troops.There, Carson rescues young Danny(Bobby Nelson)and his dog Sagebrush from a burning covered wagon after his parents have been killed by hostile Indians.Carson takes the boy and his dog to Pioche, where he leaves him in the care of Nancy Cameron(Barbara Weeks)and her father(John Elliott).Saloon owner Nick Slavin(William Walling as Bill Walling)plots with bartender Dick Temple(Kit Guard)and Dad Cameron, an unwilling accomplice, to hold up the Overland Stage, making use of information obtained by Cameron in his capacity as express agent and postmaster.Following the sucessful robery, bank president Joe Mountain decides to go to Washington and appeal for protection, but he is murder by Slavin henchman "Cheyenne" Charley(Pedro Regis.)But a band of riders wearing ponchos begin to put a crimp in the activities of Slavin and his gang.Cameron, upset by the killing of Mountain, tells Slavin he has had enough and is leaving Pioche and wants no part of his share of the $30,000 taken in the stage holdup.Slavin tells Charley, always ready for a chance to use his knife, to take care of Cameron.Slavin persuades town Marshal Houston(Gordon deMain as G.D.Wood)that Carson is mixed up with the ponchoed riders and the Marshal goes to Cameron s house to arrest Carson, but he gets away.Some of Slavin s henchmen are captured by Carson and his riders, and they confess to the crooked activities of Slavin and Temple, and also Cameron.Back in town, Charley is about to knife Cameron from ambush, but the barking of Sagebrush warns Cameron and Cameron is able to kill Charley instead, with Danny as a witness. Houston, Slavin and Temple take Danny to the marshal s office and attempt to make him tell who killed Charley, but he refuses even after Houston take Sagebrush outside and Danny hears a shot fired.Cameron comes in and confesses to killing Charley but tells Houston the whole story, and Slavin informs Houston that he is taking charge of the town, and takes Cameron to the saloon for a quick trail followed by a quick hanging. Two of Carson s riders come to the office and take Houston to their hideout, where Carson, showing his authority from President, deputizes Houston as a U.S. Marshal and tells him that his Poncho Riders will help him clean up and rid the territory of Slavin and his gang.After a pitched battle, the gang is wiped out and Slavin and Temple are taken to jail.In their cell, Slavin asks for his guitar, takes a derringer from it, shoots Temple and commits suicide.Cameron is forgiven for his forced crimes, Carson and Nancy are locked in an embrace, and Houston tells Danny to whistle for Sagebrush, who he hadn t shot at all.