What starts out as a quite promising gonzo pastiche sadly loses steam after the first act, when the script runs out of ways to sustain the hilariously insane premise. It's a real shame, because the film is made to a surprisingly high standard.
On a moon mission to promote the 2018 re-election campaign of the US President (Paul), Astronaut Washington (Kirby) is captured by a colony of Nazis been hiding on the dark side since 1945. Within their massive swastika-shaped complex, they're preparing to take over earth with their Fuhrer (Kier). Things get complicated when second-in-command Klaus (Otto) travels to earth with Washington to get supplies for the invasion. But Klaus' idealistic schoolteacher fiancee Renate (Dietze) stows away for the trip, and their mission is derailed when they team up with the president's shark-like press agent (Sergeant).
There are some great ideas in here, including a lacerating satire of right-wing governments that makes it tricky to tell which is worse: marauding Nazis or hawkish Republicans. The set-up offers continuous B-movie fun, from the Nazi's hilarious spacesuits to Earth's wacky military response. All of this is rendered with surprisingly high-quality effects, which is perhaps what makes us expect a lot more of the script than it delivers.
While there are several amusing moments along the way, the comedy simply isn't clever or consistent enough to keep us laughing. Long stretches get bogged down in distracting plot points or corny slapstick, while the cast members overplay their roles shamelessly. This wouldn't be a problem if the overall tone of the film was broader, but the strong production values never let that happen.
By about halfway through, we start waiting for the filmmakers to unleash something fiendishly clever to kick things up a gear, but they instead stretch their one gag stretch even thinner. Some of these touches are clever, such as the way moon-born Renate insists that Nazi theories will bring about world peace. Of course, she learns the truth when she finally sees all of Charlie Chaplin's classic The Great Dictator. But that sharp reference backfires badly, because that 1940 film is still the funniest and most devastating Nazi comedy ever made.