Whilst investigating the wonders of the lost world, discovering many plants and creatures thought to be extinct, they narrowly escape an attack from pterodactyls. Although barely escaping with their lives, Roxton takes great interest in nearby blue clay deposits. At night a ferocious dinosaur is about to break through the thorn bushes surrounding their camp; Roxton averts disaster by bravely dashing at it, thrusting a blazing torch at its face to scare it away. Later, all except Malone are captured by a race of ape-men. Whilst in captivity they discover that a tribe of natives, with whom the ape-men are at war, inhabit the other side of the plateau. Roxton escapes and together with Malone mounts a rescue, preventing many unpleasant deaths, including a young native who is a prince of his tribe. The rescued natives take the party to their village, then with the help of their firepower return to defeat the ape-men. After witnessing the power of their guns, the tribe wish to keep them on the plateau but, helped by the young prince they saved, they eventually discover a tunnel leading back to the outside world. During their time with the tribe, Roxton plans how to capture a pterodactyl chick, and succeeds in doing so.