On the day when Yalitza Aparicio, the star of Roma, found out that she was nominated for an Academy Award for best actress, she was in Tijuana, standing in front of the 30-foot-high barrier that separates Mexico, her country, from the United States. It was a profound moment and a symbolic victory: Aparicio, who is 25, comes from the small town of Tlaxiaco, in Oaxaca, and she’s the first indigenous Mexican to receive this kind of acclaim from Hollywood. “It’s amazing,” Alfonso Cuarón, the director and writer of Roma, told me. “We create a division every day with the people around us, and Yalitza comes from a place that is easy to put aside and forget. In Mexico and elsewhere, people who look like Yalitza are immediately ­classified and deemed unworthy. Being acknowledged by the Academy has a big impact. It’s another wall. And hopefully that wall has started to fall.”

In Roma, Aparicio plays Cleo, a nanny at the heart of an upper-middle-class household in early-1970s Mexico City. The film is autobiographical: Cuarón based Cleo on Liboria Rodríguez, his own beloved nanny, whom everyone called Libo. The family, the home, the world he depicts in Roma is a mirror image of his childhood. Cuarón was very particular about every detail—even Borras, the endlessly barking dog in Roma, had to look and act like his boyhood pet—and the search for the right woman to play Cleo was exhaustive. After seeing more than 3,000 applicants for the role over the course of a year, Cuarón was almost ready to give up. “Then Yalitza walked in,” he said. “Libo was also from Oaxaca. And Yalitza had the right attitude: Just because she was sweet and somewhat shy, that didn’t take away from the fact that she was damn strong. Her strength came through in her eyes.”

Yalitza Aparicio wears an Edith A. Miller tank; Agnona skirt.

Directed by Alfonso Cuarón; Photograph by Carlos Somonte; Styled by Valentina Collado. Hair by Manuel Oliva for Bumble and bumble; Makeup by Mónica Godínez; Manicure by Luisa Pérez Paz. Produced by Gabriela Rodriguez; Producer: Alettia Molina; Production Manager: Rodrigo Macin; PostProduction Producer: Carlos Morales; Photography Assistants: Francisco Cestac Fort, Arturo Lara Fernandez; Digital PostProduction: Claudia Lizalde; Visual effects: Fernando Torres; Swing: Jorge Chagoya, Bernardo Covarruvias; Tijuana Fixer: Adriana Santos; Gaffer: Abel Coronilla; Grips: Benito Guerrero, Javier Garcia, Raul Cerebros, Victor Oliva, Vladimir Aguirre, Mario Luis, Iris Esquer, Juan Carlos Rodriguez; Fashion Assistants: Dan Victoria Gleason, Astrid Nerio; Production Assistants: Mariel Mayorga, Carolina Machado, Armando Herrera; Tailor: Christina Madrid.

Yalitza wears Gabriela Hearst dress.

Directed by Alfonso Cuarón; Photograph by Carlos Somonte; Styled by Valentina Collado.

Initially, Aparicio had no desire to become an actress. Her older sister, Edith, who was pregnant and couldn’t audition, urged her to go to the casting call. Aparicio found the interview intriguing; she was simply asked questions like, “Have you ever been in love?,” “Have you ever been heartbroken?” Aparicio had never heard of Cuarón and had never seen any of his films (including Y Tu Mamá ­También, Harry Potter and the Prisoner of Azkaban, Children of Men, and Gravity, which won Cuarón the Oscar for best director in 2014). “I had other plans than being in a film,” ­Aparicio said, laughing. “I had just finished school and had my teaching degree. Even when Alfonso told me I had the part, I still wasn’t sure.”

The actual creation of Roma was unusual and very personal: For the entire filming, Cuarón never showed his cast a script; instead, he presented them with certain dilemmas or lines each day and often gave different actors conflicting scenarios, so they would view events only through their character’s perspective. “I had thought about making Roma for many years, but always chickened out,” Cuarón admitted. “Finally, a close friend said, ‘Stop fooling around—come back to Mexico and do a film here.’ ” After many long, very precise conversations with Libo (to whom Roma is dedicated), Cuarón searched his memories. “I compared my own recollections with hers,” he explained. “But the only way you can approach a memory is through your understanding of the present. That confuses things, and I wanted to write something with no judgement, to get to the essence of what was then and how that became what is now.”

Yalitza wears Dôen dress.

Directed by Alfonso Cuarón; Photograph by Carlos Somonte; Styled by Valentina Collado.

Yalitza wears Alternative Apparel tank top; Tory Burch skirt; Julia y Renata belt.

Directed by Alfonso Cuarón; Photograph by Carlos Somonte; Styled by Valentina Collado.

Through that process, Cuarón began to realize that his childhood experiences with Libo pointed to a larger truth about Mexico’s cultural and political heritage: its prejudice and systemic classism against indigenous people. “I now realize that growing up I had this perverse entitlement,” Cuarón explained. “I was educated that way, but it’s not anything to be proud of. Libo and I were so close, but we really came from two different microcosms. I feel terrible about that now: Libo, in my life, and Cleo, in the film, are owed a debt. Roma is my attempt to honor them, while showing how much we still owe.”

That is one of the reasons why Cuarón wanted to photograph Aparicio at the border. “The wall turns people into enemies for no reason,” Cuarón said. “Walls are pointless. Whether there is a physical structure there or not, I’m more concerned with the invisible wall that divides social classes and backgrounds. That’s a barrier we accept every day, without thinking.”

Directed by Alfonso Cuarón; Photograph by Carlos Somonte; Styled by Valentina Collado.

Yalitza wears Julio x Francisco Cancino shirt; Agnona skirt; stylist’s own belt.

Directed by Alfonso Cuarón; Photograph by Carlos Somonte; Styled by Valentina Collado.

So Cuarón imagined anonymous migrants levitating over the wall with Aparicio. And he envisioned her with a large group of migrants doing the “Zovek” position. In Roma, that storklike pose is an homage to the real-life El Increíble Profesor Zovek, an escape artist with prodigious skills who explains that, easy as it seems, maintaining that stance with your eyes closed is much harder than any conventional test of strength. In a crucial scene, a battalion of men attempt to assume the position—and one by one they fail. Aparicio, as Cleo, tries it from the sidelines and achieves it easily.

Back at the shoot, Aparicio had changed into a white cotton eyelet sundress with short puffed sleeves, admitting that in real life she wasn’t really comfortable wearing anything fancier than jeans, a T-shirt, and sneakers. Still, since Roma’s release in November 2018 (a few weeks earlier, it had been the centerpiece of the New York Film Festival), Aparicio has been dressing up and has found her voice. She now speaks eloquently about her role as a representative of indigenous people. “I went to school to be a teacher,” she said. “And Roma can educate people. It can help break the stereotype that skin color determines your destiny.”

Yalitza wears Jonathan Cohen shirt and skirt; Ancient Greek Sandals sandals; stylist’s own belt.

Directed by Alfonso Cuarón; Photograph by Carlos Somonte; Styled by Valentina Collado.

It was surprisingly cold in Tijuana, but, at Cuarón’s request, Aparicio splashed in the ocean, walked along the beach in a light shirtdress, and, without shivering, struck the Zovek pose in a tank top and chiffon skirt. In nearly every shot, the border wall loomed in the background. Nearby, on the boardwalk, people were walking their dogs and eating at small cafés. Eventually, when they realized who she was, they gathered around Aparicio, their ­newest star, and effusively complimented her. “It’s so interesting what the spotlight can do,” Cuarón observed. “Yalitza is very much like the people who are trying to cross into America for a better life. But now, because of the attention she is getting, she has become special. Yalitza could be the people at the wall, and they could be her.”

Yalitza wears Brora cardigan; Massimo Dutti skirt.

Directed by Alfonso Cuarón; Photograph by Carlos Somonte; Styled by Valentina Collado.