In the early 1900s, one of the few remaining free-ranging Indians is caught raiding a slaughterhouse for food. He turns out to be the last of the Yahi tribe.

An anthropologist from the University of Berkeley, Dr. Alfred Kroeber (Jon Voight), befriends the man, whom they name Ishi (Graham Greene). Kroeber is the only man remaining who can even speak Ishi's language.

Kroeber stalwartly refuses the offers made by the Bureau of Indian Affairs, the last of the "Wild Indian" branch, which wants to repatriate Ishi from California to a reservation in Oklahoma. Instead, Ishi becomes an employee at Kroeber's San Francisco-based museum. And Kroeber attempts to maintain scientific detachment as he studies a rare example of Native American culture.

The story is a strongly moving tale based on a true-life event. This is perhaps Voight and Greene's best acting to date. If you can see this and not be moved to tears, your heart is of iron.