The Ecuadorian Rainforest provides the backdrop for a church-sponsored mission trip gone bad. Nineteen-year-old Hope Holloway, haunted by visions, faces a series of paranormal events. She and the other young missionaries befriend and live with the Shuar Indians as they struggle with their attempts to integrate with the tribe and introduce Christianity to the children of the rainforest.

A dark shapeshifting spirit known to the Shuar as the Iwanci lurks in the jungle. It uses Hope as its conduit, forcing her to see horrible visions of torture and murder. But what does this thing want with her? What makes Hope its medium? Does her gift make her more receptive than the others, predisposed to premonitions? Was she the weak link in the chain? Hope knew the answers to all these questions and they shake her to the bone. Until now, the supernatural occurrences have just been warnings. Now the Iwanci beckons her, calling out, slicing away at her resistance; it comes to her like a beacon emanating from the forest. This time, she has no choice; she must heed its call and face it alone in the jungle. There will be great consequences if she doesn't. After a horrific, torturous encounter with the Iwanci, its message becomes clear:

LEAVE THE RAINFOREST OR DIE!

Things turn from bad to worse, when Hope and her friends drink a strong tribal hallucinogen and find themselves lost deep in the rainforest. Unable to find their way out, the group faces unspeakable evils that prowl all around them. When the situation becomes desperate, Hope conjures up her most primal instinct - survival, by any means possible!