Another Bunker style movie. And while I do have a heart for them, there is one major ingredient missing here, that would make it really good. Don't get me wrong, I don't think it's bad, I'd say it is decent, but without any real charisma from our main characters, the connection between the viewer and the "heroes" is missing.There are a couple of stabs at giving at least one of them a bit of a backstory (it's the "expert" in underground tunneling), but it's not enough to make us care too much. We know that something is seriously wrong with a bunker like that. Especially when Nazis are involved. So while the period/time piece does work, and the effects are good for a low budget movie, there could have been a better result in other departments. If you just watch it to pass time and/or are a fan of close spaced horror/action, than you could do worse