Sundance ‘26: ‘SENTIENT’ a Traumatizing Doc About the Horror of Animal Testing

A profoundly upsetting documentary, Sentient explores the multitudinous horrors of the animal testing infrastructure—not just the physical, psychological, and spiritual toll on the animals, but the damage done to the human technicians, scientists, and doctors complicit in the process, all underpinned by science that may not be as solid as it claims to be. Centered on the expansive animal testing industrial complex, particularly the role of primates and most specifically the macaque, this film from Australian director Tony Jones leans on a mission-driven talking heads format, giving space to explore both sides of the moral and ethical quagmire that is testing on creatures as sentient as we are. It strikes a potent balance between the informative and the devastating, channeling an activist spirit without sacrificing journalistic integrity.

While it’s true that many of humanity’s pharmaceutical breakthroughs owe their origins to animal testing, the impact on the animals—even when they aren’t being killed—is so visibly profound that the whole endeavor feels ethically bankrupt. Just a few clips of said testing should be enough to convince even its staunchest defenders. Beyond the morality of it all, Sentient introduces the growing argument that animal testing isn’t just cruel, it’s bad science. One scientist drops a damning statistic: over 95% of treatments that work in animal trials fall apart when tested on humans. Worse still, some drugs deemed safe for monkeys turn out to be actively harmful to people.

Jones structures the story around Dr. Lisa Jones Engel, a primatologist-turned-PETA advocate, whose decades working with primates led her to question both the ethics and efficacy of the field she once championed. We see her life working with macaques, from her pre-collegiate volunteer work in South East Asia to a decades-long tenure at the University of Washington to a years-long, grant-funded family research trip and witness firsthand the casual trauma inflicted upon these highly intelligent, highly social primates. But the film’s most harrowing moment arrives via unauthorized footage from a toxicity lab, where the torment inflicted on the monkeys is captured in brutal, unflinching detail. It’s soul-rattling stuff, enough to make any viewer wonder: how far are we willing to go, and what are we willing to become, in the name of “bettering” the human race? And that’s what a good documentary does: it shakes you to your core and forces you to confront just how easily we normalize institutional cruelty.

CONCLUSION: A harrowing but necessary watch, Tony Jones’ Sentient offers a clear-eyed look at the primate testing industry. It’s hard to endure but harder to ignore.