Anthropologist Stanley Shephard (Timothy Hutton) is brought to an arctic base when explorers discover the body of a prehistoric man (John Lone) who has been frozen in a block of ice for 40,000 years. After thawing the body to perform an autopsy, scientists discover to their amazement a real possibility to revive him and their attempt to resuscitate the "iceman" proves successful.
In the aftermath of Godzilla's attack on Tokyo and his later imprisonment at Mt. Mihara. a team of scientists discovers cells left in the rubble by the monster and collects them. A group of American militants takes a sample of their own. They attempt to escape with them, but are killed by a lone assassin codenamed SSS9, who steals the sample and departs. He boards a cruise liner and heads to the Republic of Saradia to deliver the cells to the Saradia Institute of Technology and Science. The president of the institute wants to use the cells to merge with genetically modified plants, hoping to transform Saradia's deserts to vast greenery and end the country's dependence on oil wells for wealth. Dr. Genshiro Shiragami and his daughter, Erika, are enlisted to aid with the ambitious project. However, a terrorist bombing destroys the institute's laboratory, ruining the cells and killing Erika.
Ernie Fitzpatrick is a daredevil kid who lives in Terra Dino with his best friend Max Santiago and his trouble-making sister Julia, who likes to bust him. Ernie and Julia live with their mother Sue, who has been chosen as the mother of the year, but she is overprotective of them and often makes them leave notes. Ernie is told to go to the store after school to keep an eye on it, but he disobeys orders and goes with Max to the Terra Dino Museum to sneak into a forbidden part of the area still under construction to see the bones of the ferocious Sarcosuchus. But Julia enters as well and uses a quarter from Ernie to set off the alarm. Julia is able to escape but Ernie and Max get caught by the guards, and Sue grounds Ernie for three weeks. When Ernie finds out Julia did it, he gets sick and tired of how he never gets his own way, but he decides to get his revenge by sneaking out again, but Julia discovers this and follows.
Escaping from China with a microfilm of the formula for the mysterious "Lotus X", Lord Southmere, a Queen's Messenger, is chased by a group of Chinese spies.
Far north of the Arctic Circle, a nuclear bomb test, dubbed "Operation Experiment", is conducted. Prophetically, right after the blast, physicist Thomas Nesbitt (Paul Christian) muses, "What the cumulative effects of all these atomic explosions and tests will be, only time will tell." No sooner said, the explosion awakens a 30-foot (10 m) tall, 100-foot (30 m) long carnivorous animal known as Rhedosaurus, thawing it out of the ice where it had been held in suspended animation. Nesbitt is the only witness to the beast's awakening and is later dismissed out-of-hand as being delirious at the time of his "sighting". Despite the skepticism he persists, knowing what he saw.
King Kong, after being shot down from the World Trade Center, is kept alive in a coma for about 10 years at the Atlanta Institute, under the care of surgeon Dr. Amy Franklin (Linda Hamilton). In order to save Kong's life, Dr. Franklin must perform a heart transplant and give Kong a computer-monitored artificial heart. However, he lost so much blood that a transfusion is badly needed, and to complicate matters, Franklin says there no species of ape or other animal whose blood type matches Kong's. Enter adventurer Hank "Mitch" Mitchell (Brian Kerwin), who captures a giant female gorilla, who is dubbed "Lady Kong"; in Borneo (Mitchell theorizes that Borneo and the island from the first movie were once part of the same landmass), bringing her to the Institute so her blood can be used for Kong's operation. The transfusion and the heart transplant are a success, but Kong escapes along with the female.
After a volcanic eruption on Daikoku Island, the Yahata-Maru Japanese fishing vessel is caught in strong currents off its shores. As the boat drifts into shore, the island begins to erupt, and a giant monster lifts itself out of the volcano. A few days later, reporter Goro Maki is sailing in the area and finds the vessel intact but deserted. As he explores the vessel, he finds all the crew dead except for one young man called Hiroshi Okamura, who has been badly wounded. Suddenly a giant Shockirus sea louse attacks him but he is saved by Maki who kills it with a cleaver.
The Japanese fishing vessel Yahata Maru is trying to find its way to shore in a horrible storm while near an uninhabited island, when a giant monster appears out of the island and attacks the boat. A day later, reporter Goro Maki finds the vessel intact, along with its sole survivor Hiroshi "Kenny" Okumura.
Gamera self-destructed to destroy several Gyaos in 1973, the tale picks up thirty three years later, when the son of one of the survivors of that incident finds an unusual egg, from which a baby turtle hatches. The boy, Toru, raises the creature, quickly realizing it as remarkable in that it hovers and breathes fire. The creature quickly outgrows the house, is relocated by Toru and his friends to maintain secrecy, and then disappears.
Koichi (Takeru Satō) et Atsumi (Haruka Ayase) sont amis depuis leur rencontre à l'école primaire. Ils vivent ensemble depuis qu'Atsumi est venu à Tokyo pour être mangaka. Koichi, professeur dans un club de sport, se plaint qu'Atsumi ne pense qu'au manga et à ses délais à tenir.
Police Detective Shindo (Yosuke Natsuki) is assigned to guard Princess Selina Salno of Selgina (Akiko Wakabayashi) during the Princess' visit to Japan, due to a suspected assassination plot. Although Shindo is smitten with Selina's photograph, her plane never makes it to Japan, as it is destroyed by a bomb en route. At exactly the same time a meteorite shower draws the attention of Professor Murai (Hiroshi Koizumi), who along with his team of scientists strikes out into the wilderness to examine the largest of the meteors, which has magnetic properties.
In the 1960s, two astronauts, Fuji and Glenn, are sent to investigate the surface of the mysterious "Planet X". There they encounter advanced and seemingly benevolent human-like beings called the Xiliens and their leader The Controller. The aliens usher the astronauts into their underground base, and moments later the surface is attacked by a creature the Xiliens call "Monster Zero", but which the astronauts recognize as King Ghidorah, a planet-destroying monster that had attacked Earth once before. The monster eventually leaves, but the Controller states that Ghidorah has been attacking repeatedly, forcing them to live underground in constant fear. He requests to borrow the Earth monsters Godzilla and Rodan to act as sentries against Ghidorah's attacks, in return for the cure for cancer (the English dub says the formula can cure any disease). The astronauts return to Earth and deliver the message.
After Yata (Toru Ibuki) is lost at sea, his brother Ryota (Toru Watanabe) steals a yacht with his two friends and a bank robber, the crew runs afoul of the giant lobster Ebirah, and washes up on the shore of an island, where a terrorist organization manufactures heavy water for their purposes, as well as a chemical that keeps Ebirah at bay. The organization, known as the Red Bamboo, has enslaved natives from Infant Island to help them, but the natives hope to awaken Mothra (now a full-grown moth metamorphosed from the larva that appeared in Ghidorah, the Three-Headed Monster) to rescue them.
In Crater Lake, Northern California, Dr. Richard Calkins (Hyman) is informed by his colleague Dan Turner (Garrison) that he and his girlfriend Susan Patterson (Cobb) have made an incredible discovery in a nearby cave system. The three head down and discover a system of cave drawings, including what appears to be a depiction of people fighting off a Plesiosaurus, thus providing evidence that dinosaurs existed at the same time as man. However, a flaming meteorite crashes into the lake just overhead, resulting in a cave-in that destroys the cave system and the drawings, while the three scientists are barely able to escape alive. The local sheriff, Steve Hanson (Cardella), sees the meteorite crash and radios in the incident before continuing on his patrol.