 Canadian Mounties Corporal Rod Webb (Kirby Grant) and Constable Mike Kelly (Robert Sherman), along with Rod s dog Chinook (Chinook the Wonder Dog), are sent to the Blackfoot Crossing country to find the killer of trapper Antonie Dubois, and also to investigate reports of illegal deals in beaver pelts. Mike, a rookie, is delighted with the assignment as it takes him to his home country where he again sees Sandra Dubois (Lorna Hansen),his childhood sweetheart. Posing as trappers, Rod and Mike meet Matt Oliver (Warren Douglas), introduced as a mining engineer, at Sandra s home, who is a little irked at the warm welcome Mike receives from Sandra. The undercover Mounties soon get on the trail of Morgan (Leonard Penn), Howell (John Close) and Cheval (Richard Avonde), the illegal beaver trappers. While searching for evidence in the trading post ran by MacGregor (Phil Tead), Mike is surprised by Morgan and Cheval and is killed. Rod closes the trail that reveals Oliver as the leader of the gang. Chinook takes care of Oliver, and Rod arrests Morgan and the others.