Continuity mistake: In the part when the two American officers are looking around in Anchorage, USA, and come across the dead woman at the News Studios you can clearly see her blink 2 or 3 times as the camera pans out.
Continuity mistake: When Moira is watching the submarine leave during the last scene, the deck is nearly submerged and waves are washing over it. When the shot changes to the Captain on the conning tower, the deck behind him is dry as a bone.
Continuity mistake: During the long shots in final scene as the submarine is leaving, the wind is so strong that the flag flies straight out behind the conning tower. During the close-ups of the crew, their shirts and hats show no wind at all.
Continuity mistake: Two scenes in the movie show a closeup of the tower on the submarine with a plexiglass shield in front of the actors. Both times you can make out the reflection of trees as the camera moves.