Dian Fossey was a pioneer, a renowned primatologist who dedicated her life to the study of gorillas and their protection. She became an international icon, but in Rwanda she was waging a war. This fight ultimately cost Fossey her life, and her brutal murder in 1985 remains unsolved to this day.

The series weaves together three story strands. The first is the story of Dian's life and work – her childhood, her first trip to Africa and her arrival in Rwanda where she set up the Karisoke Research Centre to study Mountain Gorillas. The second strand tells the story of Dian's murder in Rwanda and the trial of her American co-worker Wayne McGuire, who was found guilty of her murder. Wayne fled Rwanda before the trial began but was convicted in absentia. He has always maintained his innocence. We review the scant evidence presented at the trial and speak with people who were involved in investigating the murder. Finally, we will tell the story of Dian's legacy through the Pablo troop of gorillas, the offspring of gorillas who Dian knew and studied, and that survived the very worst years of poaching and habitat loss due in large part to Dian's efforts.

This stunning three-part documentary series features rare and previously unseen archival footage of Fossey in her daily habituations as she studies gorillas up-close, and includes in-depth interviews with some of her closest colleagues and friends including her research assistant, who was accused of her murder, Wayne McGuire and friend Sir David Attenborough.