Charlize Theron says playing Megyn Kelly in the upcoming “Bombshell” was harder than portraying a real-life serial killer.

Theron, who stars in the film alongside Nicole Kidman and Margot Robbie, said after a screening of the movie Sunday: “This was harder,” when asked to compare her “Bombshell” role with her role as Aileen Wuornos in 2003’s “Monster”.

The actress continued, “She’s incredibly well known. I’ve never played anybody on that level. I’ve played real people that nobody knows about so there was less pressure when I did those.”

Theron recalled thinking, “Maybe there’s somebody out there who can do this better than you can,” before adding: “But I was just really scared, too. I honestly knew her so superficially,” according to People.

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The contentious movie follows former Fox News CEO Roger Ailes, played by John Lithgow, and the women who accused him of sexual harassment.

Theron has obviously been asked a lot about Kelly while doing the promo rounds for the film.

She recently told Ellen DeGeneres she had no contact with Kelly in preparation for the role.

Theron said, “We used a lot of source material in telling and finding the story, and also spoke to a lot of women who were part of the story.

“Some of them were still working at Fox, some of them really didn’t want their names out there. So, as a team, we’ve really decided to protect our sources.”