The film begins with a summary on how the Allies are struggling to stop U-boats from sinking their freighters. The scene transfers to U-571, which torpedoes and sinks a British freighter. The crew are happy with the kill but seconds later, however, the sonar man reports to have detected high speed screws. The captain turns the periscope to sight a destroyer moving in, forcing U-571 to dive. The destroyer drops depth charges; unfortunately for the submarine, the depth charging snaps a fuel line which ignites while the engine crew attempt to patch it, setting them all on fire. Due to the amount of damage sustained, the captain orders U-571 to resurface. The captain learns from his chief who extinguished the fire in the engine room that their batteries are practically flat, both diesel engines are inoperable, and all of their engineering crew are dead. After passing word to conserve electricity, he has his radioman send an SOS to Berlin for aid.