Two men are found murdered at Garou's Landing, a small outpost in the snow-covered Canadian Northwest. One of the victims is a Mountie, the other a businessman named Bennett, whose partner Andrew Larkin becomes the primary suspect in the brutal crime. Sergeant Renfrew, assigned to the case, journeys north with Larkin's daughter Kay, who doesn't suspect that he has been ordered to bring back her father, dead or alive. Renfrew captures the accused killer but is forced to shoot Larkin when he tries to escape. This allows the real killer an opportunity to dispose of Renfrew without revealing his true identity.
Second of the eight Renfrew films, James Newill reprises his role as the stout-hearted musical Mountie. On the Great White Trail is a murder mystery, whereas its immediate predecessor was a straight action melodrama. The story's whodunit angle is well handled with a surprising twist that provides the impetus for the film's climax. Grand National's flagging fortunes sent Renfrew looking for another home, and he found it in Monogram Pictures, which continued the series with six more feature-length adventures produced by Philip Krasne and released during the 1939-40 season. - Ed Hulse