A man is at sea during the a storm when a giant octopus attacks him, the man is about to die but he is then released by the octopus. The man looks out the ships window to see a giant green man like beast fighting the giant octopus. The giant green Gargantua is called Gaira. Once Gaira defeats the octopus he turns on the ship, sinking it and its crew. The one sailor from the ship survives but the rest of the crew did not make it the man tells the story of how he was first attacked by a giant octopus then by Gaira. He says Gaira ate his crew members the doctors think that the sailor is just in shock and making up the story. When word gets out about the mans story journalist begin interviewing Dr. Stewart and his assistant Akemi who once had a captive baby Gargantua named Sanda. The journalist being asking them if it is Dr. Stewart's escaped Gargantua that ate the sailors crew. Dr. Stewart discredits all the journalist questions saying that the Gargantua Sanda would never eat humans and that Sanda would never live in the ocean if anything he says Sanda would return to the mountains where he was first discovered.
Sanda returns to where he had hid the injured Gaira and discovers that Gaira has been eating humans. Sanda begins fighting Gaira when he discovers Gaira is evil. Gaira then burst into a sprint and begins running across the country side back towards Tokyo at full speed. Dr. Stewart attempts to convince the military that Sanda is good and to focus on Gaira. The military ignores the Doctor and prepares for battle in Tokyo. Gaira arrives in Tokyo and begins to feast on humans Gaira is has adjusted to light and now looks at light as a marker to where his food is. Sanda arrives in Tokyo shortly after Gaira and the two monsters begin fighting the military sides with Sanda and focuses all fire on Gaira. The monsters end up in the ocean battling each other the military starts unleashing bombs on the monsters causing an the irruption of an underwater volcano right beneath the battling Gargantuas. The volcano then swallows the two monsters burning all their cells making it impossible for the cells to mutate and form more Gargantuas.
I find it funny that this movie comes sold "Rodan" on DVD because both movies basically have the same endings, both end with two Kaijus lava filled deaths in a volcano. The movie is great I think it is funny how this was originally intended to be a sequel to "Frankenstein Conquers The World" but they changed their minds and only reference it alittle the movie. The movie is intended to be completely detached from "Frankenstein Conquers The World " although they reference a few things. This movie really is a great movie. When I was kid and watched this movie I actually found this to be a pretty scary movie Gaira watching Gaira eating people was quite horrifying for me as a kid. I love Kaiju movies as a kid especially Godzilla but "War of the Gargantuas" was the scariest of the movies for a 5 year old me. I of course grew up to enjoy the movie much more. So if you are introducing your kids to Kaiju movies which I strongly recommend this might be one you want to save for when they are a little older depending on how easy they scare. It is very rare that I say a Kaiju movie might be scary but this is one. Something else I find interesting about this movie is the fact that Gaira was made from Sanda's cells mutating, even though at the end the two monsters are incinerated and the cells could not escape I wonder what of Sanda and Gaira's early cells. What is to stop have stopped Sanda and Gaira shedding more cells earlier? Sanda was up in that mountain and out in the wild for 5 years and they were finding fur and skin from the two monsters everywhere. How do we know that there is not more Gargantua cells out their mutating. This is one of the most popular Kaiju movies because it was first released in American theatres as a double feature on the bill with Godzilla vs Monster Zero, and it really surprises me that their were no follow ups to this movie. I strongly recommend seeing this movie if you are a new Kaiju fan and have not yet. Thanks for reading and keep a look out for my review of "Frankenstein Conquers The World " sometime in the next few weeks.