With the Nazis occupying their small town in Norway during the height of the world war, Captain Hauptmann Koening (Helmut Dantine) and his garrison face a suicidal resistance from the locals who reject all things Nazi. Dr. Martin Stensgard (Walter Huston) has been the town physician and leader with his activist daughter Karen (Ann Sheridan). Together with a fisherman named Gunnar Brogge (Errol Flynn) and Gerd Bjarnesen (Judith Anderson), the Nazis have faced stern opposition. A double-agent in the Nazi army will help the resistance find arms and stage a counter-attack on the occupying force. Though he wants to escape to England on his fishing boat, Gunnar will stay and lead an attack on the Nazi soldiers.