Forgive me for bumping this old-ish thread but I bring new information on the infamous Hitler Building, and this seems to be the most recent thread where it's come up.
The common explanation for years was that it was woefully misused WWII stock footage, but I think it's obvious that it's a model shot. August Ragone apparently confirms this in his introduction on the DVD release. (I haven't seen this feature for myself but that's what I read at the MST fan Wiki, which I guess could be wrong.) I think this actually makes it a more puzzling conundrum: why would the filmmakers of a 1960s Japanese superhero movie photograph a model building with a depiction of Hitler on it?
In 1960, filmmaker Erwin Leiser produced and released a documentary titled
Mein Kampf, about the rise and fall of Hitler. I haven't seen this movie but based on Leiser's history (German citizen who fled the country as a teenager in the windup to WWII) it seems reasonable to assume it's pretty condemnatory of Hitler and Nazi Germany. IMDb notes a February, 1961 Japanese release by Towa Co., Ltd. (then the country's largest importer of foreign films, and now a subsidiary of Toho). This would have been approximately around the same time New Toei was shooting
Invasion of the Neptune Men, released July 19, 1961.
So was the Hitler Building an advertisement for Leiser's film? Probably. The building itself is the Tokyu Cultural Assembly Hall, as confirmed by
this tweet. (Tokyu --not Tokyo-- is the name of a Japanese railway company which has dabbled in other businesses.) It was located in Tokyo's Shibuya ward before it was demolished in the 2000s (not by alien attack). There's not much in the way of English-language material about this building but according to its Japanese Wikipedia entry, it did house at least one movie theater, even in the early '60s. I can't find any evidence that
Mein Kampf was screened here, nor evidence that the building was adorned with a massive Hitler billboard. But doesn't it seem likely that it did? Why would the filmmakers invent a fake enormous Hitler ad on a real building?
The question remains, even if it was a real ad on the building, why build a model of it and include it in their film? Some Japanese fans highly regard the Neptunian missile strike sequence, such as
this blogger. He calls it "realistic" and "intense", and maybe the filmmakers realized it would have been somewhat frightening for some of the audience. The destruction of a huge Hitler billboard
is a pretty funny sight, and I'm sure contemporary Tokyo audiences would have understood the reference. It's worth noting that in the same sequence, the saucers annihilate the headquarters of Japan's liberal party. These shots are somewhat incongruous to the rest of the sequence, which depicts panicking civilians searching for cover while famous Tokyo landmarks are destroyed. It's my opinion that these two shots were inserted by the filmmakers to relieve some tension in an otherwise bleak montage. At the very least, these were probably humorous shots for the moms and dads that dragged their kids to this.
Incidentally, there's some truth to the old "World War II footage" story. I haven't seen the Japanese version of the film, but allegedly the U.S. distributors of Neptune Men did in fact insert grim WWII footage for some reason. The Brains cut these shots for the MST episode, and I'm pretty sure Dark Sky's mid-2000s DVD release excised those shots as well. Something Weird Video thankfully (?) released an unedited copy of the U.S. version sourced from a 16mm print, and lo and behold the WWII stock shots are sloppily inserted through much of the final act of the film. You can check out this version for yourself on YouTube if you're so inclined.
Additionally, there was once some speculation once that Toei's 1960 WWIII melodrama The Final War might have been the source of some of the destruction footage in this movie, but a Japanese copy of that film finally surfaced several years ago and surprisingly there's no Hitler Building. (A shot of Japan's Diet being destroyed by Neptune saucers is actually lifted from The Final War, but I don't know what else--if anything--was culled from that movie.) However, this is where things get confusing: the U.S. version of The Final War (unfortunately missing since the 1970s) reportedly inserted footage from Neptune Men, specifically shots of the saucers, here allegedly representing futuristic commie aircraft. So it's possible that the infamous Hitler Building was seen in the U.S. version on The Final War, although it's definitely not in the earlier Japanese version. See how confusing that is?