The crypto-zoological agency Monarch faces off against a battery of god-sized monsters, including the mighty Godzilla, who collides with Mothra, Rodan, and his ultimate nemesis, the three-headed King Ghidorah.
After a scientific experiment leads to the creation of a clone of Mewtwo, he sets out to destroy the world. Ash and his friends then decide to thwart Mewtwo's evil plans.