On a blistering
afternoon somewhere in the South Pacific, the United Nations research vessel
"ARCO" is on a mission to study the rise of algae growth in the ocean due
to the increase of ultra violet radiation from the sun. Unfortunately, while
in the middle of their research, the ship is caught in an approaching typhoon,
and although the crew tries to hold their course, the ship is dragged towards
an unknown island. Strangely enough, the island is not on the captain's
charts, even though these are well traveled waters. Upon approaching the
island, the ship begins to break apart. All of a sudden there is a tremendous
explosion and the ship sinks. Only a handful of the crew escapes.
A few days later as the storm
passes, the survivors, using whatever equipment they could salvage from
the ship, set up camp and wait to be rescued. No one can understand why
the island has never appeared on any nautical charts. The head scientist,
Dr. Mugato, decides that the most important goal is to secure food and water,
as they may be stranded there for a long time. Breaking into groups, they
start out to explore the island.

One group, headed by a reporter
named Musatto and his friend Kobayashi, are cutting their way through dense
vegetation when they round a hillside into a clearing and come face to
face with Godzilla! Surprisingly Godzilla shows no reaction to these newcomers,
sitting quietly on a boulder staring blankly ahead. Although frightened
and despite Kobayashi's protests, the group decides to take a closer look
for they are curious. This Godzilla looks different from the one that has
terrorized Japan for so many years. This Godzilla appears smaller, with
only a single row of plates running down his back. hoever, before
the group can get any closer, a strange whining noise comes from overhead,
and a white and blue spacecraft flies into view. Hovering over Godzilla for
a moment, the ship flies off toward the mountains. Puzzled, Musatto decides
to investigate, but kobayashi insists on heading back to camp to report what
has happened. As they return, a fading memory begins to form in their minds.
In the ocean off the coast of
Japan, near the city of Morioka, the fishing ship "S.S. Tanaka Maru" is
blown out of the water. Slowly, Godzilla rises from the ocean bottom and
heads for shore.
On the island at the survivors'
campsite, all groups including Musatto's report having encountered strange
creatures during their exploration. Some were familuar, like Godzilla,
Mothra and Rodan; others, like a four legged spike backed creature and
a giant spider- like creature, were not. All creatures showed no
reaction to their presence nor showed any sign of life. All sat quietly
staring into space. There was also a nagging feellng among the group
that all these creatures should be famillar to
them, but for some unknown reason were not. Determined to solve
the mystery of the island, Dr. Mugato, Musatto, and a small
group of survivors set off toward the mountains in the direction the
flying saucer headed, leaving Kobayashi and a small group on the beach
to signal to any passing ships.
Godzilla, having arrived in the
city of Morioka and destroyed it, slowly turns south heading in the direction
of Tokyo. General Satto of the Japan Self Defence Force, trying valiantly
to stop him, orders the deployment of the new Super X4.
The small group of explorers arrive
at a small valley between the two largest peaks on the island, having passed
many strange creatures along the way. In a clearing below, to the amazement
of the group, sit three spaceships, all of different size and design. The
first, and largest, is a white and blue saucer shaped ship with a domed
top and bottom, a blue line circling the outer rim of the craft, and small
black windows surrounding the upper dome. The sec- ond, also a saucer shaped
craft, is gray in color, consisting of a single dome on top and a flat, smooth
bottom. A yellow/white light pulsates from within its surface. The third
ship Is a gray horseshoe shaped craft, with a pair of small stabilizers at
the back and a domed observation window at the center. Next to the ships
is a large radio mast with a strange antenna atop it.
In hopes of getting a closer look,
the group slowly heads down into the valley. Musatto discovers a cave and
the group enters, coming upon a conference room filled with strange, alien-like
beings. The scientist makes out four different races: thin male beings dressed
in black and grey uniforms and wearing head antenna and wrap-around dark
glasses, female creatures in silver-metallic gowns, human-looking creatures
in orange tunics but oddly casting beetle-like shadows, and ugly ape-like
creatures in silver uniforms.
Moving unseen to within hearing
range, Dr. Mugatc Musatto, and the rest of the group discover a fantastic
plan this is the base of the Alien Alliance consisting of members from
the Empire of Kilaaks, Planet X, Starhunter M, and the Third Planet of
the Black Hole in outer space. All these aliens have tried at one time
or another to conquer the Earth, all have been defeated by Godzilla and
the other monsters of Monster Island. Banding together in 1976, they
have developed a means of isolating Monster Island from the rest of the
world, thus erasing its existance from human memory, and holding the monsters
in suspension by means of high frequency waves. For ten years they waited
perfecting their science. Using cloning technologies, they took cells from
Godzilla and mutated them into a more powerful and vicious version of the
original, sending it out into the world as their ultimate weapon. At
one time they had even tried to change history by reviving King Ghidora.
The group is discovered by a group
of X-ite soldiers and, narrowly escaping capture, they stumble upon the
old control center of Monster Island. Using the records and equipment left
behind, Dr. Mugato finds a way of jamming the high frequency waves. Afte
almost eighteen years, the monsters of Monster Island awaken.
The Alien Alliance quickly attacks
the monsters in their space ships, while a small group of X-ites and apes
try to break into the control center. Unfortunately, bott are vulnerable
to the crude but effective defence of being shot or blown up. The Xians can
succumb to a good right hook. Musatto and the other scientists also discover
the old records, as well as the actual eqipment, of the old weather control
project. Learning that the Kilaaks are susceptible to cold and the
Xians to supersonic sound, Dr. Mugato quickly begins assembling a supersonic
sound oscillator while Musatto activates the weathel control units to lower
the island's temperature.
On the surface, Godzilla and the
other monsters are taking a tremendous beating. With the Alliance using
the lasers from their spaceships, the monsters can't even get close. Suddenly,
the temperature of the island begins to drop and a light snow begins to
fall. Slowly, the Kilaak ships begin to waver. On a mountain top, Dr.
Mugato, Musatto and two assistants aim the supersonic oscillating cannon
at the Xian spaceships and fire. The Kilaak ships, weighed down by snow slowly
drift towards the ground as the Xian ships explode. Freed from the
barrage of laser fire, Godzilla blasts the remaining ships out of the sky
as Angilas tramples the Kilaaks underfoot.
Godzilla then proceeds to destroy
the radio tower freeing the island from the numbing effects of the high
frequency waves. As the monsters begin to celebrate their victory Godzilla,
sensing his other self, slowly turns toward the beach and heads out to sea.
A rescue ship arrives to pick up the remaining survivors.

Godzilla has turned the northern
section of Tokyo into an inferno. Nothing the self defence force has
used, including the new Super X4, has stopped, or even slowed the monster.
Now, with most of the JSD units destroyed, there is nothing to stand between
Godzilla and the rest of Tokyo. Godzilla slowly moves towards the harbor
district, toppling everything in his path and unleashing his atomic breath
at anything that moves. General Satto orders the last group of Mazer tanks
to form a line in front of Godzilla between the railroad yard and the industrial
centre. The tanks fire continually but to no avail, Godzilla tramples them
underfoot.
As Godzilla approaches the railroad
yard, a blue/white flame catches the back of his head, and the mighty titan
falls. Out of the harbor, the original Godzilla wades onto shore. The cloned
Godzilla quickly rises to his feet and the two creatures stare each other
down, the cloned Godzilla several times larger than the original. With a
fierce roar, the cloned Godzilla unleashes his atomic breath, catching Godzilla
in the midsection and hurling him into a building badly burnt. Godzilla
fires back, but being no match for his larger counterpart, is badly beaten.
Leaving hls opponent for dead, the cloned Godzilla turns and continues
his march towards the heart of Tokyo. Lying in a pile of rubble and
scorched flesh, as night approaches, Godzilla is still.

Out of the night Rodan appears
and diving at full speed, begins to attack the cloned Godzilla. From
all around, Angilas and Baragon from underground, Manda and Mothra from
the sea, the monsters from Monster Island appear and begin to attack the
cloned Godzilla. Unable to overcome the combined forces of Angilas, Baragon,
Mothra, Manda, Rodan, Spiega, and Varan, the cloned Godzilla begins to weaken.
As the monsters prepare to deliver the final blow, the cloned Godzilla irradiates
himself. There is a tremendous release of energy and the other monsters
fall back badly wounded.
On the shoreline, Minya is trying
to revive Godzilla when the cloned Godzilla comes lumbering toward them.
Although the attacks have stopped, the cloned Godzilla is very weak. Sensing
Minya, the cloned Godzilla charges forward. Just then Godzilla revives.
Attacking his counterpart with renewed vengeance, Godzilla cuts into
his foe using punches and kicks, slowly beating his counterpart into submission.
As the cloned Godzilla tries to fight back, one by one the other monsters
renew the attack.
Defeated, weary, and staggering,
the cloned Godzilla teeters on the water's edge. Godzilla cuts into him
with his atomic breath, there is an explosion, and the cloned Godzilla falls
face first into the harbor, a sea of green blood bubbling up from where his
body lies. The cloned Godzilla is destroyed, Tokyo is saved, and Godzilla
and the other monsters return to Monster Island to live in peace.
Out in space, a small ship slowly
moves toward Earth.