Isabel Wilkerson’s acclaimed 2020 book, Caste: The Origins of Our Discontents, is a sweeping survey of how ingrained systems of social categorization—better known as castes—have led to horrific crimes and injustices throughout history. The Kirkus Prize–nominated work addresses how such systems have been used to oppress a wide range of people, including Jewish citizens in Nazi Germany and Dalit people in India, but she specifically deconstructs and explains the many ways in which caste has subjugated Black people in the United States for centuries.

Writer/director Ava DuVernay is an accomplished documentarian—she was nominated for an Academy Award for her powerful film 13th, about race and the American prison system—but she approaches Caste in an unexpected way: Her moving and revelatory biopic, Origin, delves into Wilkerson’s life and writing process. It stars Oscar- and Emmy-nominated actor Aunjanue Ellis-Taylor as Wilkerson and opens in wide theatrical release on Jan. 19.

Wilkerson’s book was a long-awaited follow-up to The Warmth of Other Suns, her Kirkus-starred nonfiction exploration of the Great Migration of Black people from the American South to various places across the country from the 1910s to the 1970s. DuVernay’s film depicts the genesis of Caste, starting with a conversation she has with a New York Times editor about her possibly writing a story about the killing of Trayvon Martin. (Wilkerson was formerly the Chicago bureau chief at the Times, where she won a Pulitzer Prize.) She’s interested in exploring it, but is hesitant to tackle the assignment while caring for her elderly mother (Sharp Objects’ Emily Yancy).

Soon afterward, her life is upended by the sudden death of her loving husband, Brett (warmly portrayed by Jon Bernthal), and the demise of her mother a year later. As she slowly emerges from her grief, she revisits Martin’s racist murder and sees it as part of a greater pattern of human cruelty—one that encompasses such things as the 2017 white nationalist rally in Charlottesville, Virginia, in which a participant killed a white counter-protester with his car, and the horrifying oppression of the Dalit people in India, who were formerly known as the “untouchable” caste. After years of research and interviews in multiple countries, she comes to realize that societies, past and present, are driven by ingrained, complex systems of social hierarchy. As Wilkerson puts it in the book: “Thus we are all born into a silent war-game, centuries old, enlisted in teams not of our own choosing. The side to which we are assigned in the American system of categorizing people is proclaimed by the team uniform that each caste wears, signaling our presumed worth and potential.”

Caste’s power is in how it illustrates this concept, not only by highlighting headline-making tragedies, but also smaller, everyday moments of dehumanization, as when a young Black boy, Al Bright, was banned by a white lifeguard from swimming with his Little League teammates in a public pool in 1951, or when Miss Hale, a Black high schooler who moved to Texas from Alabama in 1970, was told by a white principal that he knew that she wasn’t “from around here,” because she looked him in the eye as he talked. “Colored folks from around here know better than to do that,” he said.

These and many other powerful moments make it into the film intact. Often, DuVernay dramatizes such scenes to chilling effect, as when she shows a group of Nazi officials casually and admiringly discussing the Jim Crow laws of the American South. There are also several lengthy scenes of Wilkerson and others simply talking, which is truly refreshing; the author’s explanation of caste to her cousin Marion (an excellent Niecy Nash-Betts), during an easygoing outdoor barbecue, is absolutely riveting—and a testament to Ellis-Taylor’s extraordinary talent. Other scenes compellingly combine the two storytelling styles, as when an elderly white interview subject affectingly recalls Bright being barred from the swimming pool and his own shame at not doing more; in a concurrent flashback, Wilkerson herself comforts the young Bright. It’s an unforgettable scene.

DuVernay’s dreamlike method of cycling through different eras and settings gives the narrative a steadily increasing power, and it helps her to convincingly lay out Wilkerson’s case that caste systems have caused untold grief. But crucially, it also focuses on moments of connection that defy those same systems. As the film follows Wilkerson uncovering commonalities between Black Americans, Indian Dalits, and Jewish Germans, it sharply reveals the potentially world-changing power of simple empathy. Indeed, Origin, like its source material, is a passionate call to action. As Wilkerson puts it in the book: “Once awakened, we have a choice. We can be born to the dominant caste but choose not to dominate. We can be born to a subordinated caste but resist the box others force upon us.…A world without caste would set everyone free.”

David Rapp is the senior Indie editor.