Godzilla vs. Biollante

The movie begins where The Return of Godzilla left off, with Godzilla sealed away inside of a volcano and a scientific team picking through the ruins of a ravaged district of Tokyo, searching for tissue samples left behind by Godzilla. A team of American paramilitary soldiers working for a US based genetics research company called Bio Major attempts to escape with a sample, but is overcome by a lone mercenary and the samples are stolen.

Meanwhile, in the Middle East, a Japanese researcher named Dr. Shiragami looks forward to returning home to Japan with his daughter, Erika. Unfortunately, a terrorist bombing destroys the research facility in which he works and kills his daughter.

Segue five years later. Dr. Shiragami is now a haunted dreamer, who has lately turned a majority of his attention to the study of the psychic energy of roses. A young psychic named Miki Saegusa, who also heads an institution for intuitive children, aids him in his research. Dr. Shiragami is now seen as a harmless old man who uses his scientific knowledge to satisfy his own curiosity.

However, two groups are watching Shiragami: a gang of thieves hired by Bio Major and an assassin from a Middle Eastern country called Saradia. As it turns out, Dr. Shiragami is involved in the study of Godzilla cells. It is believed by Shiragami's employers that he is aiding them in figuring out how to utilize the cells' properties to create an Anti-Nuclear Bacteria (ANB), which is supposed to be used as weapons against Godzilla. The bacteria are designed to devour all radioactive material, and should prove fatal to Godzilla, but Shiragami, unbeknownst to everyone, has been conducting his own secret experiments...

When both the thieves and the assassin catch each other breaking into Shiragami's laboratory, a gunfight ensues. It is interrupted by an attack of a giant, mobile plant that kills one man and nearly kills another. The surviving thief flees, and the assassin barely escapes from the creature's grasp. Neither group realizes that they have just encountered the result of Dr. Shiragami's secret experimentations.

The next morning a giant flower is seen in a nearby lake, and Dr. Shiragami confesses that he combined the DNA of roses with that of Godzilla. Furthermore, he confesses privately to a young official that he had, in a fit of desperate grief, added the DNA of his daughter Erika to the mutated genetic structure, so that some of the creature is composed of Erika as well. He names the plant Biollante.

Meanwhile, Bio Major anonymously sends a letter to the Diet, informing Japan's government that they have planted several bombs inside Mt. Mihara, Godzilla's current prison. If the anti-nuclear bacteria is not handed over, the company threatens to detonate the bombs and release Godzilla. With the entire country held hostage, the government is forced to comply. The trade-off with the remaining thief goes well until the Saradian agent (the assassin) shows up, killing the thief before stealing the ANB. The thief dies before he can show Lieutenant Goro Gondo and Dr. Kazuhito Kirishima how to deactivate the explosives, which are set on a timer. The bombs go off, Mt. Mihara erupts, and the mighty Godzilla is once again free.

Upon hearing Godzilla's roar, Biollante's blossom opens, and the creature begins calling out to Godzilla. Dr. Shiragami theorizes that this is because both Godzilla and Biollante are essentially the same being. With Godzilla's destination made clear, the JSDF prepare their strategies for dealing with the nearly indestructible creature. The Super-X 2, a remote controlled and stronger version of the Super-X from The Return of Godzilla, is deployed, and though at first seems effective in combating Godzilla, is eventually overwhelmed by Godzilla's heat ray, and is forced to retreat.

Godzilla reaches Biollante. A mighty battle ensues, and briefly it appears that there is a stalemate. However, Godzilla's heat ray has an adverse effect on the composition of Biollante's cells, and the plant monster begins to disintegrate from exposure to the attack. With Biollante apparently dead, Godzilla continues on.

By now the JSDF is ready, with the young Major Sho Koruki in charge of operations. It is theorized that Godzilla, running low on radioactive energy after its fights with the Super-X 2 and Biollante, will head towards the nearest operational nuclear reactor, which is located in Tsuruga, on the other side of the country. All of Japan's military is sent out to meet Godzilla at Iso bay.

Unexpectedly, Godzilla surfaces in Osaka bay, avoiding a confrontation with the JSDF. Miki Saegusa tries to help, attempting to make Godzilla turn away from Osaka. Her efforts distract Godzilla momentarily, but the force of Godzilla's will overwhelms the young psychic, and she faints. A plan is put into action, involving infecting Godzilla with the regained ANB, which Dr. Shiragami helped develop. In its final battle the Super-X 2 is destroyed by Godzilla after luring it into Osaka's business District. Here a division of soldiers, including Lieutenant Gondo, carrying rocket launchers equipped with the ANB awaits the monster. The operation is initially successful, despite the death of Lieutenant Gondo, with ANB injected into Godzilla at three different points, including its mouth. Godzilla is unaffected by the germs, and continues on.

The failure of the bacteria to work is attributed to Godzilla's low body temperature, which keeps the bacteria in a near-dormant state. If Godzilla can be heated, Shiragami theorizes, then the ANB should work. The JSDF develops another plan: lure Godzilla onto a field of microwave-emitting plates during an artificial thunderstorm, where it will be heated by the microwaves.

The operation begins, but it seems that Godzilla isn't affected by the microwaves as he crushes plate after plate beneath his feet. Just as everything seems lost, a low rumble is heard and Biollante's spores rain down from the sky. Suddenly a larger more mutated Biollante emerges from the ground. After destroying all nearby land forces, Biollante attacks Godzilla, and the two massive monsters (with Biollante being roughly 50% larger than Godzilla) fight to a standstill. Suddenly, however, Godzilla begins to wobble and, losing its balance, falls headfirst into the ocean. With the intense battle raising its body temperature, the ANB inside of Godzilla became active. With Godzilla apparently taken care of, the mortally wounded Biollante succumbs to its injuries and dies, disintegrating and once again, firing its spores into space. As the monster's remains float upwards, Dr. Shiragami sees the image of his daughter among the spores. Calling out to her, he walks forward, and is shot in the back by the Saradian agent, who is still after Godzilla's cells. Dr. Kirishima chases the agent and fights him. The agent is at a disadvantage until he is able to grab his weapon again. Unarmed, Kirishima awaits certain death as the agent, from atop an inactive microwave plate, takes aim. Suddenly the agent disintegrates, and the audience sees Major Koruki remove his finger from the button that activated the plate.

With everything resolved, the characters take a moment to reflect and relax, when a dark form rises from the water. It is Godzilla, whose body temperature has been lowered by the cool sea water. With the ANB inactive again, Godzilla is healthy again, albeit restricted to the ocean. Seemingly content with this, Godzilla turns and heads for deeper waters.

The body of Dr. Shiragami is placed inside a tent, with his superior briefly mourning him before leaving. Erika is heard to comment on the events of the film, and the movie ends with a shot of Godzilla swimming away.