In "The Lost World" by Arthur Conan Doyle, Professor Challenger and his companion's journey to South America to investigate a plateau where prehistoric animals and a tribe of ape-men supposedly still live. They discover the plateau and encounter not only dinosaurs and other extinct creatures but also an ancient Native American tribe and the ape-men. The expedition faces dangers and adventures before returning to London, where they are met with disbelief until they present evidence of their findings, including a live pterodactyl.