When Geeker morphs into a dinosaur and finds himself unable to change back, Noah must hide him in Dinopolis, the hidden city of the Dinosaurs where no human is allowed. But this brings the wrath of Mister Moloch down on Dinos everywhere, and soon Noah must choose between protecting his friend and saving his people.

Mister Moloch sets hundreds of ravenous, mechanical Cyberplants loose on Neo-Denaire, programming them to capture GeeKeR and his friends. When Becky and Noah are captured, the fuzz-brained GeeKeR must prove that he can be independent and track them down all by himself. GeeKeR's attempts at sleuthing are ridiculous in the extreme, and matters are complicated when the Cyberplants get out of control and start wrecking the whole city.