Richard Denning and Carlos Rivas are geologists investigating the eruption of a formerly dormant Mexican volcano. They find a huge scorpion nest (actually, a nest of huge scorpions). They explode a series of TNT charges to close the entrance to the nest, thinking they are shutting down
the one and only entrance. Think again, Rich and Carlos. These scorpions are lots smarter than that and realize that if they were to allow themselves to be trapped this early in the film, there would be a host of viewers screaming "cheat." The chief scorpion bites all of its lair-mates and exits
for the nightlife of Mexico City, where it intends to do the same damage Godzilla wreaks ...