In a rip-roaring journey of peril and adventure, four explorers find a lost prehistoric world in the remote wilds of South America. Huge pterodactyls rule the skies and the jungle beneath is home to lumbering stegosaurus, carnivorous dinosaurs and terrifying ape-men. If the adventurers can survive then fame and fortune almost certainly await them back in London, but in this dangerous land that defies all science and reason who knows what could happen....