An American oil tanker, the SS ''Northern Star'', captained by Capitan Steve Jarvis, is sunk in the North Atlantic Ocean by a German U-boat. Along with the First Officer, his friend Joe Rossi, they make it to a lifeboat loaded with other crewmen. When the U-Boat crew starts filming their plight, they respond with defiant gestures, and their lifeboat is rammed by the sub. The survivors swim to a raft and are finally rescued after 11 days adrift.