In 1996, near Kennewick, Washington, a suspected murder victim is identified by forensic anthropologists as Caucasian - but turns out to be almost 10,000 years old. For fifty years our picture of prehistoric America has rested on the premise that the earliest inhabitants of the Americas were east Asians of mongoloid stock, the ancestors of today's Native Americans. But the discovery of the Kennewick Man, along with several other startling finds in recent years, has thrown that once widely accepted idea into question and revolutionized the science of paleo-anthropology. It has also embroiled scientists in a bitter conflict with Native American groups who want the scientific study of early Americans halted. Who and what do Kennewick Man and others represent? NOVA is following the efforts of paleo-anthropologists work to decode the story in the bones of people who died 10,000 years ago.