In Tibet, while guiding trekkers to a holy hill, Ike Crockett discovers a bottomless cave. When his enthusiast disappears, Ike pursues her in to the depths of the earth….Inside a leper colony bordering the Kalahari Desert, a nun named Ali von Schade unearths evidence of a proto-human species and a deity called Older-than-Old….In Bosnia, Major Elias Branch crash-lands his gunship near a mass grave and is swarmed by pale cannibals terrified of light….

So begins mankind’s realization the fact that about The Descent underworld is a vast geological labyrinth riddling the continents and seabeds, one inhabited by brutish creatures who resemble the devils and gargoyles of legend. With most of Hell’s precious assets and territories to become won, a global race ensues. Countries, armies, religions, and industries hurry to colonize and exploit the subterranean frontier.

Fathom by fathom, Ike manuals an expedition — and Ali — deeper into the deadly wilderness. In the dark underground, as mankind falls from them, the scientists and mercenaries find themselves prey not merely towards the savage animals, but to their own treachery mutiny, and greed. In the meantime, on the top, a band of aged scholars scours for hints to Satan’s lifetime. Is he lurking in wait for the expedition, or can be he roaming the earth? One thing is certain: Kilometers inside the earth, evil is very much alive.