The Cuban-Spanish actor stars as famed icon Marilyn Monroe in the forthcoming psychological drama biopic by director Andrew Dominik, adapted from Joyce Carol Oates’s 1999 novel of the same name.
De Armas has previously opened up about learning to adopt Monroe’s accent for the film, revealing that she spent nine months with a dialect coach.
The actor – who is due to reprise her role in the forthcoming Knives Out sequel, titled Glass Onion – has since added that she spent three hours a day with a vocal coach while tackling 12-hour days on the set of Knives Out.
The 34-year-old told The LA Times: “It was about observing her facial expressions, her mouth, the roundedness of her lips, how she showed her lower teeth, and why the ‘o’s were like that.
“Someone’s voice is more than just a specific accent. It says so much more about a person.”
De Armas also said that she came to believe Monroe’s vocal affectations were a manifestation of her emotional needs and distress.
Asked if he was hesitant to cast De Armas given her own accent and the fact that she had only recently learnt English as a second language, Dominik admitted to having initial “concerns”.
“I had concerns, until I saw her act, then I forgot what I was supposed to be concerned about,” he said.
The filmmaker continued: “We felt that we were dealing with Norma Jeane [Mortensen, Monroe’s real name] and Norma should sound less like a cartoon of Marilyn Monroe.”
Last month, Monroe’s estate defended De Armas’s accent against amid criticism from viewers.
“Any actor that steps into that role knows they have big shoes to fill,” said Marc Rosen, president of entertainment at Authentic Brands Group (ABG) that owns the Monroe estate.
“Based on the trailer alone, it looks like Ana was a great casting choice as she captures Marilyn’s glamour, humanity and vulnerability. We can’t wait to see the film in its entirety.”
De Armas recently voiced her disagreement with Blonde’s NC-17 rating.
The film will become Netflix’s first original film to receive Motion Picture Association’s highest rating for sexual content. It is a rating only given to films with content the MPA deems unsuitable for ages 17 and younger.
“I didn’t understand why that happened,” de Armas told L’Officiel in a new interview. “I can tell you a number of shows or movies that are way more explicit with a lot more sexual content than Blonde.”
Blonde premieres on Netflix on 28 September.