Godzilla vs. Mechagodzilla (1974)

While observing a traditional Okinawan ceremony being performed by Azumi royal family descendant Nami, Keisuke Shimizu and his brother Masahiko witness her suddenly freeze in terror and collapse. Nami's grandfather runs to her and asks what is wrong, to which she replies she has seen a vision of a monster laying waste to civilization and trampling on those who try to flee. Afterward, Keisuke drops Masahiko off at Gyokusen Cave as he heads to his job at an excavation site on the island. Inside the cave, Masahiko finds a bizarre piece of metal, and brings it to Professor Hideto Miyajima at Mount Fuji. Miyajima remarks that the metal is unlike any found on Earth, and likely originated from outer space, giving it the name "Space Titanium." As Miyajima studies the metal more closely, an earthquake suddenly strikes his laboratory. Miyajima's daughter Ikuko mentions that these tremors have been occuring frequently over recent days. Meanwhile in Okinawa, Keisuke investigates a cave that has recently been uncovered, and is joined by government archaeologist Saeko Kanagusuku. Inside, they find a mural that seems to depict a prophecy, along with a statue of King Caesar, the legendary guardian monster of the Azumi royal family of Okinawa. Saeko begins deciphering the prophecy, observed in secret by two mysterious men. Saeko boards a plane for Tokyo, and runs into Keisuke on the flight, who is also traveling there to visit family. Saeko reports that she has deciphered much of the prophecy: "When a black mountain appears above the clouds, a monster will appear to try and destroy the world. But when the red moon sets and the sun rises in the west, two monsters will appear to save the people." She says she is going to visit Professor Wagura in Tokyo to see if he can help decipher more of the prophecy. One of the shady men that was observing Saeko earlier is also on board the plane, and introduces himself to Saeko and Keisuke as a freelance reporter. He says he hopes she will share her story with him, as he will "make a lot of money" if he reports on it. Just then, the passengers notice a strange cloud formation that resembles a black mountain. Saeko is concerned this is the black mountain from the prophecy.

When Keisuke and Saeko arrive in Tokyo, he accompanies her to Professor Wagura's house and reveals that Wagura is actually his uncle. That night, Wagura works with Saeko to decipher the prophecy, but the other strange man who was stalking her, Yanagawa, breaks into the house and holds her and Wagura at gunpoint, demanding they give him the statue of King Caesar. Keisuke enters the room and attacks Yanagawa, successfully disarming him in a brief fistfight before he flees the house. Keisuke tries to pursue Yanagawa, but finds he has escaped. As Keisuke stares out into the night, the other observer continues watching from a distance. The next day, Mt. Fuji suddenly erupts and expels a huge rock from its crater. The rock bursts open to reveal Godzilla, appearing unusually hostile and aggressive. Saeko is astonished to learn that the evil monster predicted by the prophecy is Godzilla. Godzilla begins rampaging through the countryside, destroying buildings in his path as he gradually makes his way to Tokyo. Suddenly, the ground opens up beneath Godzilla and he trips and falls. Anguirus soon surfaces from underground, roaring before leaping at Godzilla and attacking him. Knowing his brother is near Mt. Fuji, Keisuke drives there to try and help him, remarking how strange it is that Anguirus attacked his friend Godzilla. As the battle rages on, Anguirus slams into Godzilla with his spiky carapace and tears off some of his skin, revealing metal underneath. Godzilla retaliates and brutally beats Anguirus, finally breaking his jaw and sending him retreating back underground. Godzilla roars victoriously and continues on his way to Tokyo. Keisuke finds the road blocked by debris left by Godzilla and Anguirus' battle, and notices a chunk of metal lying nearby. Keisuke brings the metal to Miyajima's laboratory, and he identifies it as also being Space Titanium. Miyajima says he wants to get a closer look at Godzilla, and travels to Tokyo with Keizuke, Masahiko and Ikuko. There, they witness Godzilla obliterate the port area of the city with his atomic breath. As Godzilla rampages, a second Godzilla suddenly appears from underneath a building. This Godzilla roars at the other, and the two beasts begin fighting. During the battle, the second Godzilla reveals a large portion of metal underneath the other's skin. Miyajima realizes that the Godzilla that emerged from Mount Fuji is actually a cyborg impostor, or a "Mechagodzilla." With the ruse exposed, Mechagodzilla sheds its disguise and reveals its true mechanical form. Mechagodzilla bombards Godzilla with missiles from its fingers and laser beams from its eyes. Godzilla fires his atomic breath at the mechanical monster, which counters with its eye beams, causing an explosion that knocks Godzilla into Tokyo Bay and badly damages Mechagodzilla's head controls. Mechagodzilla flies away, while Godzilla vanishes. Miyajima believes Mechagodzilla is being remotely controlled by aliens, and asks Masahiko and his daughter to accompany him to Gyokusen Cave in Okinawa.

When Miyajima and the others reach the cave, they are held at gunpoint by two strange men wearing silver jumpsuits. They are brought into a secret lair inside the cave, and are greeted by Kuronuma, who introduces himself as the leader of the Black Hole Planet 3 Aliens' invasion force. Kuronuma has Ikuko and Masahiko taken to the execution room, and promises Miyajima they will be spared if he helps them repair Mechagodzilla. Kuronuma then gives the order for the alien agent Yanagawa to retrieve the statue of King Caesar before anyone uses it to awaken the monster. Miyajima reluctantly agrees, and gets to work on fixing Mechagodzilla. Keisuke and Saeko, meanwhile, begin traveling to Okinawa on board the cruise ship Queen Coral, bringing the King Caesar statue with them. Elsewhere, Godzilla is repeatedly struck by lightning, but manages to harness its electrical power to produce a magnetic field. One night, Yanagawa breaks into Saeko's cabin and steals the King Caesar statue, only to be attacked by Keisuke, who was waiting for him. After a brief scuffle, Keisuke shoots Yanagawa in the face, revealing part of his true green ape-like face underneath it. Yanagawa takes the statue and runs onto the ship's deck, pursued by Keisuke. Yanagawa ambushes Keisuke and takes his gun, and prepares to shoot him, only to be shot and sent falling overboard with the statue by a hidden assailant. Saeko runs onto the deck and finds Keisuke, telling him the statue is gone. As she and Keisuke stand on deck, the "freelance reporter" reveals himself and says the two of them should be talking about love on a night like this. When the Queen Coral arrives in Okinawa, Keisuke reveals that the statue that went overboard was a duplicate, and he kept the real statue in a safe on the ship. When Saeko and Keisuke arrive at the hotel where Miyajima and the others were staying, they learn none of them have been seen in several days. Keisuke heads to Gyokusen Cave to search for them, while Saeko stays behind at the hotel with the statue. At the aliens' base, Miyajima completes his work on Mechagodzilla, only to be thrown into the execution chamber with Masahiko and Ikuko. Kuronuma activates the chamber, which releases hot steam and produces intense heat in order to boil the prisoners alive. When Keisuke searches the cave, he finds Miyajima's special metal pipe, which contains positive and negative electrodes that allow it to destroy the circuits in machinery. Keisuke is then held at gunpoint by a Black Hole Planet 3 Alien, who is himself shot by the "freelance reporter" from earlier. The strange man finally introduces himself as Nanbara, an INTERPOL agent. Nanbara reveals that INTERPOL had been following the aliens for sixth months, and he started following Keisuke once he got caught up in the aliens' scheme. Nanbara takes the alien hostage and forces him to give them access to the aliens' base. They manage to overpower two aliens and steal their uniforms, then open up the execution chamber to free Miyajima and the others. Two more aliens arrive and hold them all at gunpoint, but Nanbara quickly shoots and kills them both.

The humans flee the aliens' base and prepare to get in Keisuke's car, but Nanbara anticipates a trap and uses a wire to turn the ignition from outside the vehicle, activating a car bomb set by the aliens. Kuronuma assumes the humans are killed once the car explodes, and prepares to launch Mechagodzilla. As dawn approaches, the moon takes on a red color and begins to set, further completing the Azumi prophecy. Nanbara tells Keisuke and the others to get the King Caesar statue and awaken the monster while he goes back into the aliens' base and deals with them. Masahiko and Miyajima insist on accompanying Nanbara, and the three of them go back into the aliens' base. Keisuke returns to the hotel to retrieve Saeko and the statue, then travels to Izumi Castle. There, they find two aliens holding Nami and her grandfather hostage, demanding they hand over the statue. Before Keisuke can give the aliens the statue, Nanbara's partner Tamura shoots and kills them both. As the sun rises, it produces a mirage that makes it appear another sun is rising in the west, bringing the prophecy even closer to completion. The statue is placed on a pedestal, and fires two beams from its eyes at a cliffside, revealing King Caesar sleeping within. Kuronuma launches Mechagodzilla and orders it to destroy King Caesar while he's sleeping. At that moment, Nanbara, Masahiko and Miyajima enter the aliens' control room, only to be trapped by their security system. The men are handcuffed and forces to watch Mechagodzilla on a monitor. Because King Caesar can only be awakened by a member of the Azumi royal family, Nami runs down to the beach and sings a sacred prayer to the beast. King Caesar awakens, and is promptly attacked by Mechagodzilla. King Caesar reflects the machine's eye beams back at it, but cannot withstand Mechagodzilla's missiles. King Caesar hides behind a mountain, which Mechagodzilla cuts in half with a beam fired from its chest. Mechagodzilla charges at King Caesar and begins savagely beating him, then throws him into a ditch. As Mechagodzilla prepares to fire its finger missiles, it turns to witness Godzilla surface from the water. Saeko remarks that the prophecy has finally come true, as Godzilla is the second monster prophesized to appear and save the world. Godzilla joins forces with King Caesar and battles Mechagodzilla, but the Earth monsters are outmatched by the machine's countless weapons. Mechagodzilla unleashes a hail of missiles and lasers at Godzilla and King Caesar, who struggle to keep their footing. Before Godzilla can finally reach Mechagodzilla, it takes off and flies into the air, blasting Godzilla in the neck with its eye beams and causing him to bleed profusely and fall to the ground. Mechagodzilla fires several missiles at the fallen Godzilla, which become lodged in his flesh. Godzilla gets back to his feet and begins emitting a magnetic field, pulling power lines into his body and pulling Mechagodzilla out of the sky. Mechagodzilla finally falls to the ground and is grabbed by Godzilla, allowing King Caesar to repeatedly attack it. Mechagodzilla tries to retreat but is weighed down by Godzilla, who pulls it back to the ground. Godzilla grabs Mechagodzilla's head and twists it around until it finally causes the machine's entire head and neck area to explode and fall off.

While Kuronuma is astonished by Mechagodzilla's defeat, Nanbara picks the lock on his handcuffs and frees his hands, then throws the two halves of Miyajima's pipe at opposite ends of the aliens' computer, causing it to malfunction. Nanbara runs behind one of the aliens and, using him as a shield, shoots and kills Kuronuma. The computer begins sparking, and triggers the aliens' entire base to self-destruct. Nanbara unlocks Miyajima and Masahiko's handcuffs, then they all escape from the base as it is rocked by explosions. As the aliens' base goes up in smoke, Mechagodzilla's wreckage explodes along with it, sending Godzilla falling into the ocean below as shards of Space Titanium fall from the sky. Godzilla surfaces shortly afterward, while King Caesar returns to his slumber inside the cliff. Keisuke, Saeko, Ikuko and Masahiko then return the King Caesar statue to its rightful place in Azumi Castle, with Nami's grandfather remarking that the spirits of the Azumi royal family can now rest in peace.