Jack and Hannah are hunted in the deep jungle by a cunning poacher, hired by Scharnhorst to prevent them from meddling with her plans to excavate an ancient train station and railroad line.
Using dynamite stolen from a deep-woods scavenger to frighten a pack of dinosaurs, the Terhune brothers inadvertently set off a huge blaze in the middle of the jungle which quickly spreads, approaching Scharnhorst's new gas wells.
An earthquake frightens a herd of Triceratops, who stampede toward an assortment of settlements. After an argument with Scharnhorst about how to handle the problem (she wants to kill them), Jack and his friends organize a Xenozoic cattle drive.
Jack Tenrec must stop a rampaging dinosaur from destroying settlements. During the adventure, he meets Hannah Dundee, the Wassoon science ambassador who has just arrived at the City in the Sea.