In 2204, the remains of King Ghidorah, minus one head, are discovered beneath the ocean.
In 1992, Reporter Kenichiro Terasawa interviews World War II vet Ikehata, who claims his military unit was protected from U.S. forces by a dinosaur on Ragos Island. Terasawa beleives nuclear testing may have caused the dinosaur to become Godzilla. Industrialist and creator of Dinosaurworld Yosuki Shindo admits to seeing the dinosaur on Ragos Island when confronted by Tersawa.
A UFO is discovered in a glade. Japanese security and intelligence officials are greeted by it’s passengers. Wilson, Grenchiko, and Emmy Kano, who explain they are from the Earth Union of the future and will meet with the Japanese Prime Minister the following day. At the meeting, they say Godzilla will return, destroy nuclear power plants, and cause Japan to become inhabitable. They are there to stop the King of the Monsters. Emmy reveals a book written by Tarasawa about a massive battle with Godzilla, a book he has not yet written because the battle has yet to occur. The people from the future plan to return to Ragos Island and remove it prior to becoming Godzilla, eliminating the monster from Japan’s history. They take Terasawa, dinosaur expert Mazaki, and Miki Seagusa of the ESP Institute. Also on the trip is andriod M-11, and three bio-engineered creatures called Dorats, which look like large, brown bats.
In 1944, the time travelers arrive just as American ships begin shelling Ragos Island. The Japanese troops, including Shindo and Ikehata, are waging a losing defense against U.S. ground troops when suddenly a dinosaur appears. The creature destroys the American troops, but is seriously injured. The time travelers watch as the Japanese soldiers honor the Godzillasaurus. After the troops leave, the time travelers remove the monster using a teleport machine. The dorats are left in the island when the group returns to 1992.
There, Wilson and Grinchiko tell them Godzilla is no longer an historic figure, but King Ghidorah is. The nuclear explosions had merged the three dorats into one giant angry creature. Thier plan was to use the three headed monster to remove Japan from a future history in which it dominates the world economy. Ghidorah is laying waste to Japan. Feeling betrayed, Emmy flees.
Shindo agrees to allow his privately developed nuclear powered and nuclear armed submarine to turn the Godzillasaurus into the King of the Monsters, but is destroyed by Godzilla. A nuclear submarine that had sunk years previously irradiated the beast, turning it into Godzilla. Meanwhile, Ghidorah continues his attack. Godzilla makes landfall. He is much larger than before because he was subjected to a higher grade of nuclear radiation than in the previous timeline. Wilson orders Ghidorah to attack Godzilla. The three headed monster blasts at Godzilla with lightning-like bolts emanating from his mouths.
Ghidorah is getting the upper hand, when explosives in the time machine are set off by Emmy, Terasawa, and M-11, causing Wilson and Grinchiko to lose control over Ghidorah. The machine though is set to automatically return to the future in the event of serious damage. Emmy, Terasawa, and the android escape the ship by fleeing in a smaller time machine. Godzilla has managed to defeat Ghidorah and uses his nuclear blast to severe one of Ghidorah’s heads. M-11 uses the teleporter to send the larger machine to the creature’s battlefield. Moments before the automatic controls return the ship to the future, it is destroyed by Godzilla.
Sapporo prepares for an attack by Godzilla. Thier defenses are useless as he smashes through the city. M-11 and Emmy return to the future to “fix” Ghidorah and bring him back to the 20th century. This time, they’ll use the golden beast to stop Godzilla from destroying Japan.
Godzilla is attacking Tokyo. Shindo, though refuses to evacuate. The same monster that saved him 50 years earlier is now destroying all he built. Godzilla recognizes the industrialist when he finds him. Shindo is incinerated with a blast from Godzilla. He continues his rampage through Tokyo, but is met by Mecha-King Ghidorah. It has a new mechanical head, wings, and torso with Emmy piloting and M-11 as the computer brains. The two monsters wage a back and forth battle, with Godzilla finally blasting the refurbished monster out of the sky, knocking Emmy unconscious. Before he can deliver the killing blow, Emmy awakens and launches several thick cables that wrap around Godzilla. Mecha King Ghidorah carries Godzilla out to sea, both of the creatures falling when Godzilla blasts at his opponant.
The smaller time machine rises out of the ocean. Emmy reveals that Terasawa is one of her ancestors as she returns to her time. Godzilla, however, is still alive.
screenplay by Kazuki Omori
directed by Kazuki Omori
music by Akira Ifukube
Human Cast: Kosike Toyohara (Kenichiro Tarasawa), Anna Nakagawa (Emmy Kano), Megumi Odaka (Miki Saegusa), Yoshio Tsuchiya (Yasuaki Shindo)
Monster Cast: Godzilla, King Ghidorah, Dorat, Godzillasaurus, Mecha King Ghidorah
LogBook entry by Robert Parson