Gael Garcia Bernal portrays Kaí, a mysterious man who emerges from the Argentinean rainforest to rescue Vania, (Alice Braga) the beautiful and spirited daughter of a poor farmer who is murdered by mercenaries who requisition his property after he refuses to sign it over to them. Taking Vania with them as their prize, Kaí tracks them through the jungle and using his knowledge of the forest and his affinity with nature he releases her while the men are sleeping and then booby-traps the jungle in anticipation of their impending pursuit. Outnumbered and alone back at her father's ranch it is only a matter of time until the men return and they'll be hopelessly outnumbered and vulnerable.