I'm not sure how else to describe it. I honestly can’t think of another film quite like this one, but it felt remarkably similar to an inexpensive, cheesy sci-fi comedy that might have played at a drive-in—and that’s something to be commended. What makes it work is its complete lack of seriousness. It's fully aware of the kind of movie it is and provides exactly what it promises, without trying to be anything more than it is. It appears everyone involved understood the situation and did their part to make the film work for what it is, rather than striving for some imagined ideal. So you end up with a comedy that’s surprisingly enjoyable. It has a ridiculous story, a corny script, and silly characters, yet somehow manages to be very good. Ultimately, when you watch it, you'll find yourself laughing, enjoying the experience, and losing track of time. However, if you anticipate something like 2001, a large production budget, or a serious political commentary, you’ll probably dislike it… though then again, why would you be watching a movie about Nazis on the moon?

Source on TMDB