'Blonde' is now playing in select theaters before streaming on Netflix Sept. 28.
In a conversation with AnOther magazine published on Tuesday, the actress, 34, said she and the Blonde crew left a handwritten note on Monroe's grave on the first day the film began production.
"We got this big card and everyone in the crew wrote a message to her," de Armas recalled. "Then we went to the cemetery and put it on her grave. We were asking permission in a way."
"Everyone felt a huge responsibility, and we were very aware of the side of the story we were going to tell—the story of Norma Jeane, the person behind this character, Marilyn Monroe. Who was she really?" the Deep Water star added.
De Armas also discussed the process of embodying such a powerful persona, which she admits bled into her personal life at times.
"The weight of it stayed with me for sure," she explained. "There was no way to unplug because I'd get home and study for the next day and then Andrew was on the phone until midnight."
"I would go to sleep and dream I had long conversations with her," the Knives Out star added. "I was thinking of her so much, some days I would go home and have dinner and as I was washing the dishes I would just start sobbing, crying and crying, because I had this terrible feeling—I knew I couldn't fix it."
The No Time to Die alum previously said she believes Monroe's spirit visited the film set during production, telling reporters at the Venice Film Festival, "I truly believe that she was very close to us. She was with us," according to Entertainment Weekly. "I think she was happy. She would also throw things off the wall sometimes and get mad if she didn't like something. Maybe this sounds very mystical, but it's true. We all felt it."
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