![‘Sentient’ Review: The Ethics Of Animal Testing Undergo A Fierce Debate [Sundance]](https://cdn.theplaylist.net/wp-content/uploads/2026/01/24173936/sundance-Sentient-Still_3.jpg "‘Sentient’ Review: The Ethics Of Animal Testing Undergo A Fierce Debate [Sundance]")
A warning to any animal lover. This is a difficult watch. From the opening moments of a documentary called “Sentient,” as a hidden camera takes us deep inside the cold, unforgiving hallways of a nondescript laboratory, layers of cages, each containing an animal soon revealed to be primates, emit wails of confusion and claw at their surroundings as workers begin to remove each from their respective dwellings in preparation for…something.
It’s not hard to guess what that might be. As one particular creature escapes the grasp of several ready to administer anesthesia, it quickly becomes apparent that some version of animal testing is about to happen.
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Some may already possess awareness of the controversy surrounding the field. Still, as outlined in “Sentient,” a history lesson on how this practice came to be occupies several minutes of film following that grim opening, and the rationale to primarily rely on primates in the testing of vaccines, medications and even high doses of astronaut-grade radiation stems from the DNA they closely share with the humans that, by any measure, should be treating their hairy counterparts with dignity and respect. While the film does eventually hear from a number of both current and former industry veterans, it’s one figure in particular around whom the narrative largely revolves, and there’s no shortage of eloquent musings she has to say.
Dr. Lisa Jones-Engel is that figure, someone with sights set on a career in medicine from a young age and, following the influence of the late Jane Goodall, spent years with her husband overseas working in a pioneering capacity alongside macaques as she clung to the belief that the capture and eventual experimentation on these animals was, ultimately, for the greater good. Footage taken during this period shows this woman as she lords over a pile of research documents, talking about how what she’s doing is for the best, though even in these decades-old clips, she can barely conceal the doubt so clearly draped across her weary face.
Her groundbreaking work would eventually lead her, along with her growing family, to the University of Washington, home to the Washington National Primate Research Center and where the seeds of her chagrin would truly take root. Her mentor, as seen in archival video taken during his time at the U of W, would state in interviews that, as much as he may ethically oppose using primates for various forms of testing, it would be just as ethical to stop.
Indeed, the other side of the debate receives just as much attention throughout, with attention placed on both the eradication of polio and the AIDS epidemic of the 1980s, and on how important such research was to those directly impacted during this period. Meanwhile, a ballroom full of testing supporters, when asked to raise their hands if they had ever experienced remission from cancer, respond that such remission could have been made possible only by animal testing, eliciting a collective smile as each sits firm in their unwavering support.
Even those who still work in this field, including the provider of the hidden camera used at the beginning and scattered throughout the film’s third act, seem more than willing to share their thoughts. One continues to stand behind the work, one lives with the weight of every day on the job, and in this regard, it’s easy to see behind the expression each wears.
The bond is undeniable. Regardless of personal standpoints, forming a connection with every patient quickly becomes inevitable, to the extent that the euthanasia one performs once the animal has outgrown its usefulness often results in a specific form of PTSD manifesting amongst the testing staff. There’s terminology used to describe such end-of-life procedures, mentioned in “Sentient,” alongside interviews in which the manner in which the animal is equipped to cease all functions is described in detail, with one particularly horrific moment enough to make a viewer take pause.
As dour these segments might be, when one mentions how the final thought of a monkey, following a lifetime of exhaustive testing and living space reduced from the vast plains their species desires to a box the size of a telephone booth, might be, “What have I done to deserve this, “it’s here that “Sentient” somehow manages to become all the more upsetting. Oh, and those scenes of a mother needing to be rendered unconscious so her babies can be forcibly, permanently removed from her care?
It’s a lot to take in, all the way to the final, tearjerking minute. All sides of the fight receive their moment in the spotlight, even as its shown how despite our similarities, the translation of successful animal testing in no way guarantees an identical process in humans, or when the Trump administration announced a plan to move away from what’s seen as an outdated practice as new technology enters the equation, explicitly designed to produce the same results without the need for flesh and blood.
There’s a natural flow to “Sentient,” even as the film shifts between those in support and those in opposition with seemingly reckless abandon, with any footage placed well and the words of every speaker making for a captivating experience. In the best possible way, director Tony Jones has created the documentary version of a car crash; you don’t want to look, but you can’t bring yourself to look away. It’s impossible to walk away without having learned, at the very least, something, another point of praise for a film as heavy as it gets. [A+]
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