NEW YORK, NY.- Ava DuVernay and Aunjanue Ellis-Taylor were in the middle of shooting their new drama, “Origin,” when Ellis-Taylor gave the writer-director some last-minute homework.

The two were hours away from filming a scene in which the actress’ character, Isabel Wilkerson, the Pulitzer Prize-winning author of “Caste: The Origins of Our Discontent,” gets into an argument with her husband, Brett (Jon Bernthal), after a party. Ellis-Taylor felt the scene required a few extra beats of dialogue and asked DuVernay to write some.

“She said, ‘I think we need something here,’” recalled DuVernay, who agreed to write the new material during her lunch break. “I trusted that she, inside the character, knew what she was talking about.”

That level of trust, amid the daily high wire act of a modestly budgeted production — filmed at a brisk pace across three continents — was typical of a collaboration that DuVernay called her deepest with an actor since working with David Oyelowo on “Selma,” her breakout film released nearly 10 years ago.

In Ellis-Taylor, DuVernay saw an actor of “outsized power,” capable of giving her imaginative take on the making of Wilkerson’s book a vital emotional anchor. Ellis-Taylor, nominated for an Oscar in 2022 for “King Richard,” saw in DuVernay a “director of consequence,” perhaps the only person who could successfully adapt “Caste” — a bestselling, Big Idea book that links systems of oppression in the United States, Nazi Germany and India.

“She is a freedom fighter,” Ellis-Taylor said. “There are consequences and repercussions because of the work that she does, and that separates her, I believe, from most artists.”

In a joint interview last month in Manhattan, the actor and filmmaker discussed finding the heartbeat of the critically acclaimed drama in personal material not included in the book, the transformative influence of shooting in Berlin and Delhi and the importance of Bernthal’s swagger. These are edited excerpts from the conversation.

Q: Ava, one of the fascinating things about this film is that it’s not a typical adaptation. It’s part adaptation and part bio-drama, tracking a harrowing period of Wilkerson’s life while she was researching and writing “Caste.” What led you to make that decision?

AVA DUVERNAY: I needed a character who could personalize the concepts — the psychology and the history and the legacy of caste. I didn’t know (Wilkerson), but I watched interviews with her and thought that she could be the one to take us on this journey. When I pitched her, I told her I would need to hear the stories that are behind the book, none of which are in the book, and she very generously shared them with me. As a writer, I think she instinctively knew that I would need freedom to interpret the story. And she gave me that.

Q: Aunjanue, you didn’t meet Wilkerson before filming. What did you draw on to create your performance?

AUNJANUE ELLIS-TAYLOR: I watched her famous TED Talk about “The Warmth of Other Suns” (her award-winning 2010 book about the Great Migration) and her interviews with Bryan Stevenson and Michael Eric Dyson. But (“Caste”) was my bible. Her writing is so intimate and personal — you can feel her blood coursing through every sentence. Often, she’ll be talking about a subject, and she’ll say, “This happened to me, too.” I felt like I knew where she was coming from just by reading her words.

Q: The film is inventive in the way it turns the book’s ideas into visual entertainment. Scenes of Wilkerson honing her thesis with friends, family and colleagues alternate with dreamlike, historical reenactments of some of the central stories she is citing. How did you figure out what was enough and what was too much when it came to unpacking the concepts and the history?

DUVERNAY: One thing that was really important was just to have people to talk about it with. I had a handful of people who were living inside the book with me and who were fluent in its ideas. Aunjanue; my producing partner, Paul Garnes; my cinematographer, Matt Lloyd; and my friend Guillermo del Toro. David Oyelowo read the script and was really helpful, too. They helped me figure out how to turn the book into a springboard to conversations about these things.

Q: Wilkerson’s husband, Brett, is mentioned only briefly in the book’s epigraph and acknowledgments, but he is central to the movie’s emotional arc. What made you think of Bernthal?

DUVERNAY: As soon as Aunjanue said yes, we had the challenge of who could hold the frame with her. Jon not only believed in the project, he was very interested in working with Aunjanue, specifically. (The two co-starred in “King Richard.”) He flew out to Savannah, where I was working, just to meet with me, on his own dime, which is something that doesn’t happen to me very often. Plus he had the appropriate swagger — that was important. I had to be able to look at this guy and think, “He can pull her.”

ELLIS-TAYLOR: He is just a lovely and generous human being. He supported me in a way that our performances felt lived in — they didn’t feel performed.

Q: Did filming on location — in Berlin and Delhi — influence the way you told the story, or even your understanding of the text?

ELLIS-TAYLOR: In every way. Because Isabel going to India, smelling things that she had never smelled before, learning things that she had only heard about, all of that stuff was happening to Aunjanue, to me personally. I’m not a scholar, but I was able to get a sense of what that experience was like. I’m so grateful to Ava for insisting that we go to these places.

DUVERNAY: Paul Garnes and I, we always knew that, even though we were on this very finite independent budget, we needed to get to the real places. We needed to be in the real square of Bebelplatz (in Berlin), where the books were burned. (In 1933, a Nazi group and supporters burned more than 20,000 blacklisted books in the square.)

Could I have found a square in Georgia to do it and enjoyed the tax credit? Probably. Would it have felt as emotionally resonant as it was for everyone when we were actually standing there in the place where it happened? Certainly not. Or to go to Delhi, in a country that is closely associated with caste, and to be there as an African American and just fall into a sea of beautiful Brown people. To understand that even as I look at them all and see them as one, they don’t see each other that way? That these divisions have been ingrained in their faith, culture and society?

For me, coming from a society where it’s all about skin color, it helped me understand that we as human beings will always figure out how to bifurcate and categorize and create hierarchy. That’s the core of so many of our problems. If you don’t know that, then you’re treating the symptoms and not the disease.

Q: Ava, there’s a way in which this movie feels like a synthesis of all the work you’ve made since your narrative feature debut more than a decade ago. There’s a meditation on grief à la “I Will Follow,” an intimate love story like in “Middle of Nowhere,” and historical figures involved in the struggle for racial justice as in “Selma” and “13TH.” Were you conscious of that while you were making it?

DUVERNAY: I wasn’t. But my editor, Spencer Averick, who I’ve worked with since my first movie, said that to me at one point. I feel like everything I’ve done before, even shooting internationally for “A Wrinkle in Time,” which is a whole different discipline, prepared me for this film. I felt really in the pocket. There was nothing on set that was like, “I don’t know how to do this scene,” or, “I don’t know what’s next.” It was, “I got this,” which was an overwhelmingly fulfilling experience.

I felt like, if tomorrow I decided I just was going to be a painter or, I don’t know, go back to being a publicist, I could, because making this movie was so satisfying. In the past, I would finish a movie and feel like, “I hope they like it!” But this time was different. I think a lot of that feeling comes from using their money — the Hollywood machine. This was made outside of the machine, and it felt very free and very liberating.

This article originally appeared in The New York Times.