A mysterious man, known as Kai (Gael Garcia Bernal), emerges from the Argentinean rainforest only to witness a poor farmer being mercilessly slaughtered by mercenaries sent to requisition his land. Taking the dead man's grown-up daughter, Vania (Alice Braga) with them, they retreat back into the jungle. Using his innate knowledge of the forest, Kai sets off in pursuit and rescues Vania while the men are sleeping, setting booby-traps in his wake to hinder any attempt at recapture. Outnumbered and alone back at the ranch, it is only a matter of time until the mercenaries will return. All they can do is wait, and prepare...