With the clouds of war gathering across Europe, at the Norwegian fishing village where she is vacationing with her brother, Robert (Robert Coote), and their father (Sir Cedric Hardwicke), an admiral in the British Navy, Judith Bowen (Anna Lee) falls in love with the quiet Erik Toresen (Paul Muni). After the Germans invade Norway and brutally beat a villager they've accused of spying, Erik organizes a guerilla army to resist the occupation. Forced to escape when his identity is exposed, he stumbles upon a nearby German airbase and, after making the treacherous passage to England to alert Admiral Bowen, returns with Robert to carry out a daring - and deadly -- commando raid to destroy the airfield and free his countrymen.