Excellent study of WWII merchant marine crew sailing between the U.S. and Murmansk, Russia, the only supply line then open between the Western Allies and the Soviet Union. Bogart plays a loyal, brave, and rugged first mate to idealistic captain Massey. After their first tanker is torpedoed, and the two barely survive an eleven-day ordeal at sea, Massey and Bogart are given a spanking new Liberty Ship, with most of their old crew members as well as a sharp Navy gun crew. They sail with a massive convoy en route to Murmansk, but are repeatedly hounded by U-boats. Bogart and company battle through the Nazi attacks, managing to sink a surfaced sub by faking a shipboard fire and ramming the sub, then shooting down several German bombers on the approach to Murmansk. A powerful document of a class of men given little due for their heroic role during WWII, the film lives up to its title--there is action aplenty. The film earned an Oscar nomination for its original story.