A century ago, the people of the Mashco Piro fled deep into the Peruvian Amazon to escape the cruelty of colonialist rubber companies. They cut all contact with the outside world, entering an isolation they still haven't abandoned. German filmmaker/biologist, Carl Gierstorfer, turns around in front of the forest, looking back at those who want to contact the isolated Mashco Piro: missionaries, gold miners, drug traffickers, ordinary villagers. Only a group of dedicated anthropologists stands between outside forces and the Mashco Piro, themselves torn between curiosity and fear. When a murder happens, Gierstorfer is there to document the story.