The 49th Parallel was written by Emeric Pressburger and directed by Michael Powell just before they finalized their partnership as The Archers, when they would take co-credit for writing, directing and producing their movies. The British government wanted a film that would help convince America that the fight against the Nazis was also America's fight. Powell and Pressburger convinced the government to film the movie in Canada. They created an episodic adventure story which gave ample opportunities to make the case that the war against Nazi values was also an American war. Powell and Pressburger enlisted several well-known British and Canadian actors to play at scale, and had to shoot their scenes around these actors' scheduled return to Britain. You'll find one fairly weak spoiler, the plot, underfoot.
In 1940, a German U-boat is sunk in Hudson Bay in northern Canada. Six crewmen escape. They are led by Lt. Hans Hirth (Eric Portman), a dedicated Nazi who realizes that if they can make their way across the border (the 49th parallel) to the United States, which was neutral, they'll be returned to Germany. If they are caught in Canada, they'll be interred for the war's duration. The film is about how they try to make it to the border and the different kinds of Canadians they encounter. There are four major episodes, tied together with smaller adventures. In episode one, the Germans find a small Inuit village and some French Canadian trappers (Lawrence Olivier, Finlay Currie). They treat the Inuits as substandard humans; the Inuits and French Canadians resist and some are shot as the Germans get away. In the second episode they encounter a Hutterite farming community led by Peter (Anton Walbrook, himself a recent Austrian refugee from Hitler). The message here is that Canadians have come from all different countries and backgrounds, and that they value cooperation and peaceful acceptance of differences. In the third episode they come across a writer (Leslie Howard) who feels the war is so far away it hardly makes a difference. But when the Germans show contempt for what they see as his weakness and destroy his paintings and books, he arouses himself and fights back. In the last episode, Hirth is the remaining German and has hidden in a train's freight car going across the border at Niagara. He finds himself sharing the car with a Canadian army deserter (Raymond Massey), who finds his patriotism. In an action that is clever and courageous, the deserter ensures that Hirth is caught in Canada and then declares his readiness to return to his unit and fight.
As usual with a Powell/Pressburger film, it is extremely well crafted and untypical of its genre. Not all the German's are shown as villains. Their journey as they get closer and closer to the border arouses a certain kind of enthusiasm. You don't really hope they make it, but you are caught up in their efforts. And while the movie is made up of episodes carefully crafted to send home a message to the American audience, it holds together as a well-told tale. More than 70 years later, it still is an effective movie. Partly this is because of the acting. Although Olivier uses an awful, pseudo-hearty French accent, the other actors hit their marks. Howard is very good as a too civilized intellectual who finally understands what's at stake. Eric Portman does a fine job of playing a ruthless, committed Nazi, but also a man who is shrewd and resourceful. Anton Walbrook is excellent as Peter, the wise leader of the Hutterite farming community. And Niall MacGinness is very sympathetic as one of the German crew, a young man who used to be a baker and now would like to stay with Peter and the farmers.