When people think of kaiju, they usually imagine Godzilla and the other monstrous progeny from Toho Studios. Others might prefer Kadokawa Daiei's Gamera, and his child-friendly supporting cast. It would be a rare fan indeed who thinks of Nikkatsu Studios' sole contribution to the genre. Gappa, the Triphibian Monster ((大巨獣ガッパ / Daikyojū Gappa), also released as Monster from a Prehistoric Planet, appeared in 1967, and hasn't been seen much since.
The film combines the plots of King Kong and Gorgo, replacing their titular monsters with a cross between a bipedal dinosaur and a cockatoo.
A crew of young scientists and journalists head to the south seas looking for exotic animals that will populate a tropical-themed resort built by Playmate magazine. The drama of our first sighting of a possible monster gets immediately undercut by the reaction of the humorous sidekick character, informing us that the film will be played heavily for laughs. Some sources claim the film is an intentional parody. It's difficult to tell with late-60s daikaiju.
Our crew lands on an island inhabited by a B-movie tribe, painted Japanese extras surrounded by items suggesting Polynesian and African cultures. Although the film expresses some anti-Imperialist themes, its depiction of people deemed "primitive" is no less racist than old Hollywood's.
The invaders capture the local monster and remove it from the island, over the inhabitants' objections. The captive creature's far larger parents are soon in pursuit. City stomping ensues. A toy military engages the big beasts. The film's model work is impressive. Other effects are, to be charitable, adequate.
Gappa retains little popularity. It's not up to the standards of the best daikaiju, it doesn't tie in with other, more popular monsters, it's not very original, and, if intended as parody, it's not particularly funny.