Revealing mistake: In one scene just before the attack on a big Hunter the young captain (Jürgen Prochnow) is sitting with his charts. Beside him he has got a glass of beer standing. The sub lurches heavily right and left in the hard weather, but the surface of the liquid stays the same.
Revealing mistake: In many scenes and screenshots you can see that make-up was made sloppily: the faces of the undead Germans are rotting green, but their necks still retain a 'live' color. (00:52:20)
Revealing mistake: Billy, a young village boy, wants to join the army and fight in the war, but he is under the 18 y/o age requirement. He's supposed to be about 15 or 16 years old, but it's quite obvious that the actor playing him is in his early 20s and definitely looks old enough to join.