Northern Pursuit
After a German U-boat drops off Nazi saboteurs, RCMP Corporal Wagner (Flynn) captures the leader, Colonel Hugo von Keller (Helmut Dantine), the only survivor after an avalanche wipes out the rest of the group. When left alone with the Canadian Mountie, von Keller discovers that Wagner speaks German and is of German ancestry, and tries to persuade his captor to help him. After being taken into custody, von Keller leads a jailbreak from a prisoner of war camp, enlisting other German soldiers in his escape. Wagner, seemingly under suspicion by the RCMP of being a Nazi sympathizer, asks to be discharged from the force and is contacted by Ernst Willis (Gene Lockhart), a real enemy agent, who hires him as a wilderness guide.
Wagner and his new confederate set out for the north by train, while a pursuing Mountie who makes contact with Wagner is killed by the agent. Wagner is taken to von Keller and convinces him that he is loyal to Germany and can guide him and his companions through the Canadian wilderness to a mysterious destination. His fiancee Laura McBain (Julie Bishop) is held as a hostage to ensure his loyalty but Wagner, acting as a double agent, manages to send a message to headquarters to alert them of the Nazi saboteurs' plans.
Fellow Mountie Jim Austin (John Ridgely) follows their trail, but is spotted and killed, along with Willis and an Indian porter, before the group reaches a mine shaft where bomber components have been secreted before the war. The bomber is assembled and takes off for its mission: to bomb the main arterial waterway between the United States and Canada to disrupt transatlantic shipping of war materials. Wagner manages to escape, climb aboard the aircraft to shoot the crew, and parachute to safety before the bomber crashes. After recovering from a wound he received during the skirmish on board the aircraft, he and Laura marry.
intrigue, murder