Nick is worried that one of Godzilla's egg might have survived the events of the 1998 Godzilla movie. When Godzilla's offspring hatches indeed from a single surviving egg, Nick and his science team known as "H.E.A.T." must stop it.
It turns out that Godzilla's offspring, also named Godzilla, thinks Nick is its parent, since he was there when it hatched. Nick and his team use this to get Godzilla to help them fight a new giant mutant threat - angry deep-sea squids.
Sadistic billionaire Maximillian Spiel is capturing mutated monsters and hosting death matches between them. His latest unwilling contestant is Godzilla.
H.E.A.T. must stop Mimic, a creature that can mask itself as anyone it touches. It was created in a secret genetic experiment conducted by the French in the Amazon jungle and has only one goal in mind - to reproduce and take over.
Deep-Dweller, a giant mutated creature that partially resembles a fish and partially a frog, attacks the boats and ships near the coast of New Jersey. A sleazy local promoter unwisely uses this to his advantage.
Japanese military believes that Godzilla is a threat to the world and plans to kill it. Tables turn when giant mutant King Cobra lets itself loose on Tokyo.
