Nim, a baby chimpanzee, was taken screaming from his sedated mother days after his birth in 1973 at the Institute for Primate Studies in Oklahoma, then given to a large New York City family to be raised among humans.
Nim Chimpsky, named with some irony for the MIT linguist Noam Chomsky, was part of a great experiment: to see whether he could learn sign language and communicate.
The initially adorable animal played with his human siblings, slept in a bed and even nursed from his adoptive "mother's" teat. But as he matured, Nim became unmanageable, destroying furniture, biting those who loved him and behaving just as nature intended, like a wild animal.
Nim wreaked havoc, biting his teachers, and lands in a New York City medical lab. In the end, he was abandoned at a sanctuary among chimpanzee brethren he had never known.
His story is told in an HBO documentary, "Project Nim," which will air Dec. 20.
Based on the book "Nim Chimpsky: The Chimp Who Would Be Human" by Elizabeth Hess, the film paints a poignant picture of an animal capable of human emotion: love, jealousy and even the capacity for forgiveness.
The film, directed by James Marsh ["Man on a Wire"], won a top prize at the Sundance Film festival in 2011, and was the darling of animal rights activists in limited theatrical release last year.
But Marsh said he was less interested in advocacy than telling a unique story about an animal and how the treatment by his human caretakers reflects man's potential for good and evil.
"Essentially, we are capable of cooperation and kindness and all kinds of positive emotions in the world, but we also have this hubris," Marsh, 48, said from his offices in London. "It's a kind of 'Franken-story' in a way, about kindness and material instincts and scientific ambitions."
Chimps play a large role in human research. They were first in space, helped develop hepatitis vaccines and were crucial to early studies of HIV-AIDS.
Support for chimp research has been on the decline since Nim's death in 2000, and the National Institutes of Health has now found most invasive experimentation to be unnecessary, according to a recent report in Scientific American.
NIH stopped funding at several research centers in September and has relocated only a small number of them to sanctuaries, according to the Washington Post.
Nearly 1,000 other research chimps are still languishing in government custody, according to advocacy groups such as the Great Ape Protection Project.
"The big sin, in my view, is [the scientists] didn't think beyond what they were doing and what in the end ... would happen to Nim when he gets to be 5-years-old," Marsh said. "Even children know chimps get big and strong."
At the film's start, Columbia psychology professor Herb Terrace brings Nim to live with one of his former students, Stephanie LaFarge, and her brood of seven children in New York City.