Sydney Possuelo spent his career defending Brazil's isolated tribes, and this third episode of the series Amazon: Last Call follows him into the Javari river valley, where settlers, gold prospectors, oil crews, and loggers had spent decades pushing into indigenous land. As head of FUNAI's Department of Isolated Indians, Possuelo doubled the officially protected indigenous territory in two years, expelled settlers and missionaries from tribal land, and walked into Korubo territory to negotiate an end to decades of violence between the tribe and outsiders. The film uses his own footage of those first peaceful contacts, moments when families who had only known ambush and reprisal found reason to trust a stranger. Numbers frame the stakes throughout: six million indigenous people lived in Brazil in 1500, roughly 817,000 remain today, and the 1,300 languages once spoken across the country have fallen to about 170. The Zoe people, protected under Possuelo's watch, appear as one case where intervention arrived before an outside industry did.