Naomi Watts assumed a daunting duty when she undertook the role of the late Princess Diana in the biopic Diana. At the film's London premiere, Watts discussed the pressure of playing the British icon and how she prepared for the role.
Watts admitted that she had "major anxiety" approaching the role and felt the immense pressure of the role while deciding if she would accept it and then preparing for it. However, she said that once she got around to playing the role, she was at ease.
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"It was all the prep and also the wrestling with the decision of 'Should I do this or not?' but once you're in it, you're there and committed," Watts said.
In order to adequately portray Princess Di, who died at the age of 36 in a highly investigated car crash in Paris on August 31, 1997, Watts perused profuse amounts of available footage of the former Princess of Wales to examine her idiosyncrasies.
"It took a good six to eight weeks of listening to every bit of available footage there was," Watts revealed. "I focused heavily upon the [Martin] Bashir interview. We'd go for walks in the park and jogging and listen to it as I went to sleep at night."
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The interview that Watts deeply studied was conducted by Bashir on the BBC show Panorama shortly after Princess Di and husband Prince Charles announced their separation. Watts said it was not only informative of Diana's life but also revealing of her nuances.
"It was incredibly helpful. There was not only great information about the backstory of her character, but also how she moved her face and the sounds [she made] and the way she took breaths and all that," said Watts, who was born seven years after Diana.
Undertaking such a well-known figure was a delicate task, but the production crew and Watts' co-stars had high praises for her execution of the character.
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"She's even better than I thought she would be," said director Oliver Hirschbiegel. "She was my first choice, and I honestly don't know anybody who could pull it off like she did. She surprised me. ... Sometimes [I] forgot to say 'Cut!' because it was like I was watching a ghost."
Watch the full video above from the London premiere of the Princess Diana biopic Diana, in theaters in the U.K. on September and coming to the U.S. on November 1, for more of Watts' costars' reactions to her performance.