In the early days of World War II, a German U-boat is sunk in Canada's Hudson Bay. Hoping to evade capture, a small band of German soldiers led by commanding officer Lieutenant Hirth attempts to cross the border into the United States, which has not yet entered the war and is officially neutral. Along the way, the German soldiers encounter brave men such as a French-Canadian fur trapper, Johnnie, a leader of a Hutterite farming community, Peter, an author, Philip and a soldier, Andy Brock.

Leslie Howardas Philip Armstrong Scott
Laurence Olivieras Johnnie, the Trapper
Raymond Masseyas Andy Brock
Anton Walbrookas Peter
Eric Portmanas Lieutenant Hirth
Raymond Lovellas Lieutenant Kuhnecke
Niall MacGinnisas Vogel
John Chandosas Lohrmann
Freddie Young