I think it’s fair to say that this film scrapes the bottom of the kaiju barrel, being something of a cheap knock-off of several other films, such as Rodan, Godzilla vs. The Thing, King Kong vs. Godzilla, and especially Gorgo. Gappa features a mostly incoherent plot punctuated by shot-for-shot remakes from the above-named films. Nothing new under the sun.
There are some racist and sexist overtones to this film that were probably anachronistic when it was made, and are even more so today. Cast portraying a primitive Polynesian island culture were in a Japanese version of “blackface,” while there’s something of an urban legend that there was a line of dubbed dialogue in some versions of this film that said something to the effect of:
The monsters are attacking Tokyo. Fortunately they are attacking the Negro [or Black] section of town.
This is almost certainly not the case–it seems that a version of the film containing this inflammatory line has never surfaced.
The film is often rightly criticized for some equally tasteless dialogue in which the leading female character struggles with life outside the home and contemplates a plan to “go back to Tokyo and learn to cook. Marry some little office worker. Have babies. Stay at home and wash diapers.” As the adventure concludes, she decides it’s all just too much, and announces this is now her new life plan. Oy.
The Kaiju Cast covered this film in their Daikaiju Discussion back in April, and one thing the gang came away with was that the producing studio, Nikkatsu, did not have a good appreciation for the kaiju film genre, and was trying to make a quick buck with Gappa. That’s likely true. Tempting to think Nikkatsu was some cheap studio based on Gappa, but instead, Nikkatsu is Japan’s oldest film studio having been producing and distributing films in Japan for over a century now. So they should have known better.
I think the Kaiju Cast Gang said it best: if you have 90 minutes to kill, and an appreciation for obscure little films, and no expectations for character development, this might be a film for you. It’s on YouTube (the AIP version, anyway), which is the version I watched: