Deep beneath the sea, Godzilla sleeps only to suddenly have the earth's tectonic plates shift, the resulting energy engulfing Godzilla. He awakes in the Mesozoic era, dinosaurs fleeing from his towering form. A handful of tyrannosaurs attack Godzilla but are brushed away by Godzilla's tail. Elsewhere a titanic space monster hunts dinosaurs for its dinner. When it spys Godzilla, the monster senses a challenge and attacks.
The monsters battle, unaware of the sudden approach of an object from space, a giant meteor. The meteor slams into the earth, sending a destructive shockwave across the world. As Godzilla fades back to his own time, the space monster tries to escape earth but is engulfed in the shockwave.
On the bottom of the sea, Godzilla awakens, the tip of the space monster's tail still clenched in his claws.