Paleontologist Grant Coleman and activist Janaina Silva are recruited by Thana Katsoros for a top secret expedition, one in search of a live Apatosaurus on a plateau deep in the Amazonian rain forest. But their plane crashes short of their destination, and the entire group faces a terrifying fight for survival. This isolated area hosts unknown animals more fearsome than they'd expected, including giant ants and flesh-eating pterosaurs. Even worse, Katsoros' agenda has more to it than meets the eye, and Grant soon fears that it doesn't include all of them getting back alive. Will any expedition members survive to be rescued, or will they be devoured by the creatures indigenous peoples call the monsters in the clouds?