Blue Pete, secretly chosen by the Mounted Police to capture an Indian murderer, in his characteristic way picks up the trail and follows it into the mountains. He becomes involved in a bank-robbery that earns him a new and implacable enemy who dogs his path throughout the chase of the murderer-a perilous, unrelenting chase in the depth of winter. Disguised as an Indian, Blue Pete moves from tribe to tribe, helped and hindered by the red men. He faces zero cold, wild animals, and flying bullets, and all the time he must keep secret the task he works at. Finally, he faces a dilemma where duty and instinct struggle for mastery.