anis Carter was 25 when, in September 1976, she responded to a bulletin-board ad for a job as a part-time caretaker of a chimpanzee. The job was relevant to Carter’s interests as a graduate student in the primate studies group at the University of Oklahoma, and could help pay for school. It was also mostly hands-off; the caretakers, psychologist Maurice Temerlin and his wife, Jane, relayed instructions via note left on the kitchen counter, save for one hard rule: no physical contact with Lucy, their 11-year-old chimp. Lucy had other plans. The chimp, raised as the Temerlins’ “daughter” as a part of a foolhardy, 60s zeitgeist experiment on the limits of nature versus nurture, immediately challenged Carter’s ability to hold the boundary. “She was formidable,” Carter recalls in an expansive, disarming interview that forms the backbone of Lucy the Human Chimp, a new HBO Max documentary on the primate used as an idealistic science experiment and the caretaker who stood with her to extraordinary ends. A “very precise” signer with a 120-word vocabulary in American sign language, Lucy was “very arrogant, very condescending” about Carter’s inability to understand her. One day, Lucy motioned to Carter that she wanted to groom her. In a tense moment recreated in the film, Carter dropped the touch boundary. When Lucy asked for grooming in return, Carter reached her fingers through the chain-link cage. It was “a very special moment for me,” she recalls in the film, “and has nothing to do with theories of psychology or language or anything. It was our moment.” This foundational moment of intimacy anchors Lucy the Human Chimp, a deceptively moving, sensitive first-person account of an intense, unusual inter-species bond. The 79-minute film breezes from Carter’s weird college job to a story of tragically misguided idealism and, ultimately, a portrait of a singular friendship – a testament to loyalty and the fuzziness of boundaries between our closest animal cousins and ourselves. In 1977, the Temerlins decided Lucy, despite only having ever known humans, should live as a free chimpanzee in an African nature preserve. Carter accompanied the Temerlins to the Gambia on what was supposed to be a three-week trip to help Lucy adjust to her new home. She never went back; Lucy, extremely depressed by the upheaval and disappearance of her human parents, unable to forage and unwilling to ditch her human diet for leaves, needed her friend. Carter extended her trip by a couple of weeks, then a couple of months, then moved to an uninhabited island in the Gambia River with Lucy and two other chimps unable to survive in the wild without help. She stayed on the island, with her family of eventually 10 rehabilitated chimpanzees and without other humans, for over six years. “They got on as beings, and that’s clear,” the film’s director, Alex Parkinson, told the Guardian. “That’s the same as all the chimpanzees on the island – they all got on as one family. And it’s such an extraordinary thought that Janis is probably the only person who’s done this in the whole world.” Underlying this extraordinary bond was scientific idealism gone awry. The first third of the film replays, through the Temerlins’ home videos and archival news footage, Lucy’s mini-celebrity status as boundary-pushing experiment in the 1960s. She was born in 1964 in an American roadside zoo, and was taken from her sedated mother at two days old to be raised by the Temerlins as a test of natural instincts’ malleability, in line with the brash, pioneering exploits of the decade. At the time, the field of primatology was in vogue as an empirical – and photogenic – inquiry into questions of evolution and cognition. Pioneering primatologists such as Jane Goodall made headlines and inspired careers; primates with limited ability to communicate via sign language covered magazines. Lucy herself, once in the + 36Gambia, was the subject of an episode of Mutual of Omaha’s Wild Kingdom, a Sunday primetime staple. The Temerlins’ experiment – raising Lucy as close to human as possible – was part of this “general exploration of what it means to be human, and what are the boundaries of our capabilities”, said Parkinson. “What is that dividing line between animal and human? On paper, back then, it makes kind of sense,” he said of Lucy’s adoption. “But obviously now, looking back on it with today’s lens, it’s completely wrong and immoral and doesn’t happen any more, and rightly so.” The early days were TV-special cutesy – excerpts of the Temerlins’ home videos collected in Lucy the Human Chimp show Lucy in a diaper, cuddling her parents, eating oatmeal with a spoon, traipsing about the living room. “We wondered how chimp she would turn out to be, or how human?” Maurice Temerlin’s journal entry reads in voiceover. The tragedy is barely concealed – to no one’s surprise, Lucy’s captivity became increasingly untenable with age. The “loving family home”, Jane Temerlin laments in voiceover, became “impossible for her to live in as an adult”. (Jane was interviewed remotely for the film; Maurice Temerlin died in 1988). Parkinson believes, however, that the Temerlins “best intentions are borne out by the fact of how they viewed Lucy as their daughter. They genuinely loved her as their daughter. And they tried to do right by her and put her life right subsequently.” “It took a lot of persuading for her to talk about it,” Parkinson said of a remote interview with Jane, as it’s “an extremely emotional subject” for both her and Carter. “I think it profoundly affected them in good and bad ways. And it’s a kind of thing they haven’t really absorbed, they haven’t really gone into great detail with it within themselves since it happened.” The Temerlins and Carter wanted Lucy to be “independent, free, to have choice,” Carter recalls in the film, but it was tough, almost unfathomable going. The film’s final half dramatically recreates Carter’s time on the island (played by Lorna Nickson Brown), which she only left, by boat, every few weeks for supplies. (The reliance on dramatic recreations and Carter’s interview became necessary, according to Parkinson, once Covid lockdowns precluded further interviews with experts, academics and other figures in Carter’s life.) Carter had no camping and minimal outdoor experience; she once found a rat decomposing in the water supply she’d used for days. The chimps were dependent on her leadership for food and emotional support. Frightened and confused, they slept above her mosquito net canopy during the early months, fearfully defecating on her bed at the unfamiliar jungle sounds. The group adjusted, survived, melded as a family untethered from human measures of the passage of time. “I don’t know if I ever became a chimp, so to speak,” Carter says in the film. “But I do think that our personalities and our cultural tendencies all met together at some point and we were just who we were.” Carter only left when a male chimp, an offspring-like figure, attacked her as an assertion of primal dominance. She set up shop across the river, and later returned one more time to visit Lucy, who embraced her tightly, a moment captured in an iconic, tender photograph. Weeks later, a search party found Lucy’s scattered remains on the island, cause of death unknown. Carter stayed in the Gambia, working in chimpanzee rehabilitation as the island’s population bloomed to over 100 chimps. At the film’s close, she recalls the deep feeling of inner peace and interconnectedness that coursed through her years on the island, sacred moments recalled by the beauty of each sunset. “How often do you get a chance to live like that today?” she asks. Then, mirroring many a clip of Lucy, she covers her eyes with her hands. Lucy the Human Chimp is available on HBO Max in the US and on Channel 4 in the UK