NOVA travels deep into the Amazon wilderness in search of a mysterious tribe- a tribe that dismembered and partially ate three prospectors in 1976. Locating the group, NOVA lives with them for three months, gaining insight into the customs and beliefs of a people whose lifestyle has not changed for centuries.

Ten million years ago, an enormous volcanic eruption buried much of what is now Nebraska in up to 10 feet of ash, preserving countless skeletons of prehistoric big game animals. NOVA joins the discoverer of this treasure trove to learn what life was like when a lot more than buffalo roamed the West.