The actress stars as Bernie Madoff's wife in the ABC miniseries Madoff

By Emily Strohm
Updated January 28, 2016 04:20 PM
MJ Kim/Getty

Blythe Danner only met Ruth Madoff once before the actress portrayed her in ABC’s new miniseries Madoff, but Danner’s encounter with her isn’t one she will soon forget.

“It was really interesting because I felt she was fragile,” Danner tells PEOPLE in this week’s issue. “And how could she not be having gone through all of that.”

After it was revealed in 2008 that Ruth’s husband Bernie Madoff was behind the biggest Ponzi scheme in history, defrauding his clients of nearly $65 billion, the couple’s eldest son Mark committed suicide in his New York City apartment exactly two years after his father’s arrest. Then in 2014, their second son Andrew died following a battle with lymphoma.

“I couldn’t get over the depths of the tragedy of it and how many people were affected and the boys,” says Danner. “It was hard to comprehend.”

For more from how Danner prepared for her role, pick up this week’s issue of PEOPLE, on newsstands Friday

Though the actress, 72, says Madoff understandably “wasn’t thrilled” about the miniseries being made, (HBO also has a film in the works starring Robert De Niro and Michelle Pfeiffer titled The Wizard of Lies) she agreed to meet with her anyway.

“It must be painful to have to relive it,” says Danner. “Obviously she had been through the mill. But she was lovely and just composed. Her daughter-in-law had said how much her kids enjoy being around her and you know as a grandmother it’s a very nice thing to hear.”

Madoff airs Feb. 3–4 at 8:00 p.m. ET on ABC.