In a world where Godzilla never met his end to Doctor Serizawa's Oxygen Destroyer, his later attack on a Tokai village nuclear power plant forced the country to move to green energy. It isn't enough to power the country, so plasma energy is created. But 1996, Godzilla is attracted to it, and in his rampage, Kiriko Tsujimori's Major is killed. Swearing vengeance, Kiriko rises to an important position in newly formed G-Graspers and recruits independent technological engineer, Hajime Kudo. They plan to get rid of Godzilla through Dimension Tide, an artificial black hole that would swallow the King of the Monsters whole.
But in a test on an abandoned school, a portal is created and an egg is laid by a large insect that flies through it. A innocent boy moving to Tokyo unwittingly takes the egg; he is unable to keep it hidden, and dumps it in the sewer, where it floods Shibuya and unleashes the Meganulon upon the world. The Dimension Tide project gets derailed when the Meganulon metamorphose into Meganula and attack Godzilla to drain away his power. Godzilla escapes the black hole and moves toward Tokyo, where the Meganula who have taken his power give it to a monster that could take the King of the Monsters' place as the ultimate threat. Can Godzilla defeat the fast and wicked Megaguirus? And can the G-Graspers swallow Godzilla in the Dimension Tide when the satellite it's on begins to fall to Earth?
This film introduces the first human character to climb onto Godzilla's back in the main film franchise and begins the Millennium tradition of introducing older veterans in older, more authoritarian roles. Although it was well received by fans overall, the film tanked at the box office in Japan, selling fewer tickets than any Godzilla movie since Terror of Mechagodzilla. Like Godzilla vs. Biollante, this set the tone for reintroducing older, popular monsters in future films.
The film provides examples of
- Action Girl: Kiriko Tsujimori, who climbs onto a swimming Godzilla and risks her life so the failing Dimension Tide would target Godzilla. Megaguirus as well is a nonhuman example.
- Alternate History: Unlike other Godzilla movies, which reflected reality and kept Tokyo as Japan's capital, Godzilla's original rampage caused Japan to move the capital to Osaka.
- Animal Nemesis: It's pretty obvious that after her superior officer was killed in the prologue, Tsujimori declares Godzilla her personal "Moby Dick".
- The Bus Came Back: This film marks the second appearance of the Meganulon since being introduced in Rodan forty-four years prior. Now, they're also shown in the Meganula imago stage, as well as introducing the matriarch form, the titular Megaguirus.
- The Cat Came Back: The artificial black hole that Godzilla is sucked into at the end of the film buys Japan, at best, a couple of Godzilla-free weeks before he reappears and presumably rampages again in The Stinger.
- Corrupt Corporate Executive: Motohiko Sugiura, who admits that a secret plasma energy generator was housed in the science institute... which was the reason for Godzilla's attack in the first place. He does say that the generator was shut down, but either way, Godzilla knew about it.
- Eaten Alive: A pair of teens are eaten whole by a Meganulon.
- The End... Or Is It?: Godzilla's been defeated! The Meganulon are gone, and so is Megaguiurus! But what's been causing earthquakes? IT'S GODZILLA!!!
- Extreme Graphical Representation: The program Kudo uses to fix all the faltering tech is represented by a little man in a jetpack flying through a digital space and shooting corrupted data patches with a laser.
- Flying Firepower: Megaguirus flies at supersonic speed and is able to fire a ball of radioactive energy from her tail.
- Funny Background Event: When the G-Graspers at the end are celebrating, someone grabs Kudo by the injured arm, resulting in him wincing in pain. It's a darkly entertaining contrast to everyone else's celebrations.
- Giant Flyer: Megaguirus.
- Hell Is That Noise: Megaguirus' shriek.
- Implacable Man: Godzilla himself. Seriously, being attacked by energy sucking bugs, and being hit with a freaking miniature black hole is nothing to him in his quest for a secret energy reactor.
- Jump Scare: A scene shown from Godzilla's POV where Megaguirus suddenly Flash Steps in his face.
- Kill Sat: The Dimension Tide, designed to be mounted on a satellite, fires black holes. It would be overkill against any foe but Godzilla.
- Lightning Bruiser: Megaguirus is able to dodge and weave around Godzilla's attacks, close the distance, then fight him to a standstill up close. It's only when Godzilla brings out his atomic breath that she goes down.
- No One Should Survive That: At the end of the movie, Godzilla somehow survives being sucked into a blackhole (although considering the weapon previously opened a rift in spacetime, it's probably he merely got teleported).
- Oh, Crap!: Megaguirus has two. The first is when Godzilla jumps on her, and the second one is when Godzilla finally catches her tail... in his mouth.
- Prehensile Tail: This is the ONLY film in the Godzilla franchise in which Godzilla possesses one of these. He uses this it to catch Megaguirus in mid-flight just as she's about to sting him.
- Considering that this is the same Godzilla from Gojira, he does not die at the hands of Daisuke Serizawa's Oxygen Destroyer (nor if that existed).
- One that hits full Series Continuity Error levels: in the opening it's explained that Godzilla has a drive to rampage towards nuclear reactors that forced Japan to go green and create plasma reactors as an anti-Godzilla measure... and then at the climax it is discovered that Godzilla is targeting the new Japanese capital of Osaka because it has a plasma reactor. Further specifics are not given on why the reactor type that supposedly shouldn't attract Godzilla all of a sudden attracts Godzilla (other than the fact Godzilla rampaging through whichever is the current capitol of Japan is a franchise standard) and all characters reacts like this has always been a fact.
- Slasher Smile: Megaguirus seems to sport one at various moments during her battle with Godzilla.
- Solar Punk: As a notable background plot point, Godzilla's constant rampaging through Japan to get to nuclear reactors to feed from forced the country to invest in alternative power sources that hopefully won't attract Godzilla. In the end, the massive efforts to make such a switch were All for Nothing: Godzilla will still go for reactors, be they nuclear or plasma... or, at least, the gigantic plasma reactor that a Corrupt Corporate Executive decided to hide smack in the middle of Japan's relocated capital and Godzilla marches towards in the third act.
- Spared by the Adaptation: As mentioned above, the Godzilla in this movie the the original Godzilla. Therefore, either Godzilla managed to evade the Oxygen Destroyer, or Dr. Serizawa would not budge on his refusal to use it.
- Story Reset: set after the first film, disregarding previous movies.
- Suddenly Significant City: At some point the capital of Japan was changed from Tokyo to Kyoto courtesy of Godzilla's constant rampages.
- Sugar-and-Ice Personality: Kiriko, who's quite cool to the flirtatious Kudo and very focused on the mission. However, she's kind to children, respectful of Professsor Yoshizawa, and doesn't want to endanger her teammates. Also, it's hinted she begins to respect Kudo, and maybe even return his feelings.
- Team Mom: Professor Yoshizawa. Warm and kind, she's a prominent figure in the Dimension Tide project and has the respect of the noncomforming Kudo and the cool Kiriko. She even breaks up a fight between the two when Dimension Tide first fails.
- Too Dumb to Live: The squad who tries taking on Godzilla with bazookas. You're going to take a weapon designed to destroy tanks, and use it against something that has a reputation for destroying tanks by the hundreds?