The book is a fantasy adventure novel. It is set on a new planet Xanus which is being surveyed by an international geological team. When they are attacked by aliens a rescue mission is sent under the command of John Fallon. After the shuttle crashes into swamp lands hundreds of miles from the intended landing site, the crew are faced with a daunting journey on foot, beset every step of the way by fierce carnivores, savage tribesmen and several hostile alien life forms. Many of the crew lose their lives and the book follows the hazardous adventures of both Fallon and his second in command Phil Travers, who become separated early in the narrative.