There were many things any actress would have had to consider to embody the late royal for Chilean filmmaker Pablo Larraín's film and the American star has shared a big challenge she faced in preparing for the role: Diana's accent.
WATCH: Kristen Stewart says she was physically affected by playing Princess Diana
The 31-year-old spoke with her Happiest Season director, Clea DuVall, for an interview with InStyle back in 2020, in which she opened up about getting into character for Spencer.
"The accent is intimidating... because people know that voice, and it's so, so distinct and particular," Kristen revealed about her process. "I'm working on it now and already have my dialect coach."
The star, who became famous through her role in the Twilight films, also said she'd been doing extensive research in preparation for the role.
Kristen Stewart as Princess Diana in Spencer
"I've gotten through two and a half biographies, and I'm finishing all the material before I actually go make the movie," she shared.
"It's one of the saddest stories to exist ever, and I don't want to just play Diana — I want to know her implicitly. I haven't been this excited about playing a part, by the way, in so long."
Spencer delved into the breakdown of Diana's marriage to Prince Charles and will specifically focus on a three-day period in the early '90s during one of the princess's final Christmas holidays at Sandringham. The movie will also highlight the love Diana had for her sons, Prince William and Prince Harry.
"It's about finding herself, about understanding that possibly the most important thing for her is to be well, and to be with herself and by herself," Pablo previously told Deadline about how the film will revolve around Diana.
Emma Corrin portrayed the late royal in The Crown
"That's why the movie is called Spencer, which is the family name she had before she met Charles." Jack Farthing portrayed the role of Prince Charles in the Oscar-nominated film.
Kristen's comments about portraying Diana echo those previously made by Emma Corrin, who portrayed Diana in season four of Netflix's The Crown, which was released in November 2020.
In an interview with British Vogue, the 26-year-old spoke about the connection she felt with Diana. "I feel I've got to know Diana like you would a friend," she said. "I know that sounds really weird, but I get a great sense of companionship from her."
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