Gorillas in the Mist: The Story of Dian Fossey (1988)

A Kentucky woman, Dian Fossey, is inspired by an anthropologist Louis Leakey to devote her life to the study of primates. Travelling into deepest Africa, Fossey becomes fascinated with the lives and habits of the rare mountain gorillas of the Rwandan jungle. She becomes so preoccupied with her vocation that she loses the opportunity of a romance with National Geographic photographer Bob Campbell. 
 
Appalled by the poaching of the gorillas for their skins, hands, and heads, Fossey complains to the Rwandan government, which dismisses her, claiming that poaching is the only means by which some of the Rwandan natives can themselves survive. She rejects this, and dedicates herself to saving the African Mountain gorilla from illegal poaching and likely extinction. To this end she forms and leads numerous anti-poaching patrols, and even burns down the poachers' villages and stages a mock execution of one of the offenders. Fossey is mysteriously murdered on December 26, 1985, in the bedroom of her cabin, but her actions to help save the gorillas paid off greatly, and the species is saved from extinction.