Charlize Theron is getting some of the best buzz of her career for channeling Megyn Kelly in “Bombshell,” but the Oscar-winning actress admits she almost turned down the role.

“I was shit scared,” Theron said during a question-and-answer session following a Manhattan screening of “Bombshell” on Sunday. Partly, she was worried about portraying someone who was “incredibly well known.” But Theron also recoiled from a newscaster who spent the bulk of her career on Fox News and who was fired from NBC for making racist comments.

“She’s conflicting,” Theron admitted. Moderator Alisyn Camerota pressed Theron, noting that she had portrayed serial killer Aileen Wuornos in 2003’s “Monster.”

“This was harder,” said Theron. As a producer on the film, she admitted she wondered if “there’s somebody out there who can do this better than you can.”

“Bombshell” certainly taps into the post-Harvey Weinstein zeitgeist. With its portrait of...