Trivia

The cast was deliberately kept indoors continually during the shooting period in order to look as pale as a real submarine crew would on a mission at sea.

There was no "Class VII C" submarine left from World War II, so the crew had to build the whole interior from scratch using original plans from that time. It was mounted on a large pivot to simulate a moving submarine. * U-995 is the only remaining Type VIIC submarine. She has been on public display at Laboe, Germany since 1971.

The cast received extensive drills on how to run through the submarine (to quickly shift its balance) like an experienced crew.

The original German version has 6 episodes.

1: Operation Atlantik 2: Auf Suchkurs 3: Der erste Angriff 4: Himmelfahrtskommando 5: Auf Grund 6: In der Heimat