They are called the Orang Pendek, masters of the steamy Sumatran rain forest. Henrik Kooper watched his father die at the brutal hands of the orange-haired ape men. Having barely survived helping twins Natalie and Austin McQueen discover and destroy the beasts lurking in Loch Ness, it's now his turn for vengeance. Within the treacherous jungles of Sumatra lies the fabled lost city of Gadang Ur. Its secrets are guarded by a savage band of Orang Pendek who lord over the strange and deadly creatures of the hidden land. Utter madness is the lifeblood of Gadang Ur. Henrik's journey into darkness will take them to the ragged edge of hell on Earth. Some places were never meant to be discovered.