Dr Forle is a scientist on a river station deep in the heart of the South American jungle: the last inhabited point before the impassable interior. He is studying the eerie forest glades that the local tribes call `devil's gardens'. Who or what has created these cursed and poisoned places? The answer, he hopes, will change the way we think about life itself.

But as The Devil's Garden opens, work on the station is thrown into chaos by the arrival of a ruthless Colonel and a sinister Judge. They claim to be registering the indigenous peoples to vote and yet that night Forle witnesses an act of torture that he cannot ignore. From that moment on, he is drawn deeper and deeper into a world of brutality and corruption until he finds himself in the midst of a small war involving remote tribes, renegade soldiers, cocaine growers and the woman he has come to love.

When one of his assistants is murdered, Forle is forced to abandon his life's work and take sides. What kind of a man is he?