Fur thieves, who murder trappers when they refuse to give up their pelts at a low price, occupy the attention of the Royal Northwest Mounted Police. The leader of the gang is Victor Renaud, also the mayor of the small Canadian town where the gang is headquartered. Lucky Kerrigan is broken from the mounted service for apparent disobedience to orders, which results in the death of a fellow Mountie. Lucky, working undercover, aids the Mounties in rounding up the gang and gains back his uniform, and also the love of Gabrielle Renaud, Renaud's sister who was unaware of his criminal activities.

Krag Sabine has aroused the wrath of all the ranchers by stealing their land with the aid of his henchmen, led by Ace Barco; when Lafe Martin objects, the outlaws shoot him down. Lucky Randall promises Ann Martin he will avenge her wounded father. He sets up headquarters on the Martin ranch and sends for Bob Merritt and his men, the Texas Playboys (Jesse Ashlock, Leon McAuliffe, Cotton Thompson, Junior Barnard and Luke Wills). Krag organizes his remaining men for an attack on the ranch. Lucky's men get the upper hand but Krag escapes with Ann as his hostage.