Michelle Pfeiffer says she'll never play a real person again after portraying Betty Ford in The First Lady

Michelle Pfeiffer has scored a Cool Rider, been the Bat's meow, and been sprinkled with Stardust — but nothing prepared her for portraying Betty Ford in Showtime's new drama The First Lady.

Not to say she wasn't prepared.

"I had three scripts running," the actress says in EW's latest Around the Table video, which she filmed with costars Viola Davis, Gillian Anderson, Kiefer Sutherland, and Dakota Fanning. "I had my one script that had all of my notes. And then I had my other script that I would constantly revise with the new changes that came along. And then I had another one for something.... I don't remember what it was for."

"The week?" suggests Fanning, who first starred with Pfeiffer in 2001's I Am Sam and plays Betty Ford's daughter Susan in First Lady.

"It was an outline of the time breakdown and the scene numbers so that I had a quick reference," continues Pfieffer, who had to jump around to different moments in Betty Ford's life while filming. "And I laminated it and it was sort of this accordion. It was very colorful.... It was folded out and everything."

"Just a little bit OCD," jokes Anderson, who stars as Eleanor Roosevelt on the series.

Murray Close/SHOWTIME; Hulton Archive/Getty Images Michelle Pfeiffer as Betty Ford in 'The First Lady'; the real Betty Ford in 1976

This isn't the first time Pfeiffer has played a character based on a real person — having starred as teacher LouAnne Johnson in Dangerous Minds and Ruth Madoff in Bernie Madoff biopic The Wizard of Lies — but it may be her last.

"I said I would never do it again," Pfeiffer says having wrapped First Lady. "It's just, it's very, very weighty. And it's with you all the time. Every choice you make, and you just want to honor the person that you're playing and you want to be as authentic as possible, knowing that there will be times where you're not and you can't be. I'm never doing it again."

Still, she's "proud" to have honored the first lady's legacy.

"I didn't know half of the contribution that Betty Ford made," she says. "Of course, like most people, I knew of her struggle with alcohol abuse and drug addiction, and her founding the Betty Ford clinic, but that's really kind of the extent of it. And I mean, is if that isn't enough, there's so much more to her. I'm really honored that I was given the opportunity to share that story with everyone."

To hear more from the cast of the new series, check out EW's full Around the Table interview. The First Lady airs Sundays at 9 p.m. ET/PT on Showtime starting April 17.

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