Born in the Montana mountain ranges, Rex loves nothing more than to take his kayak out on a river, the faster and more powerful the better. When he gets the opportunity to tackle the well-named El Furioso in southwest Colombia, he is thrilled. In Colombia, he meets Myriam Calambs, an indigena, who has lived along the El Furioso all her life. Though she loves its rushing waters, she dreams of leaving to get an education so that she can help her people. Her dreams, and her very survival, are in the balance when she and Rex are caught up in the clash with paramilitaries.