Bernie Madoff made headlines when he was arrested in 2008 for conducting the largest Ponzi scheme in history that robbed thousands of people — including Holocaust survivor Eli Weisel — of their life savings. The con man pleaded guilty to 11 federal counts in March 2009, and has been serving an 150 year prison sentence ever since.

Now, Hollywood legend Robert De Niro is bringing Madoff's story to the small screen with an HBO original movie, The Wizard of Lies, directed by Barry Levinson. Even though De Niro is often cited as one of the best actors of his generation, he was given the seemingly impossible task of explaining how Madoff could fool so many people for so long and make it believable that this man really exists.

"It doesn't explain anything to say he's a sociopath. I think what you'll see in Bob's performance [as Madoff] is how plausible con men like this are," Diana B. Henriques, a journalist and consultant on the film, explained during the Wizard of Lies panel at the Television Critics Association winter previews Saturday. "A friend once told me that a Ponzi schemer can do a perfect impersonation of an honest man. That's what you'll see here."

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The hardest part for De Niro to understand was, how did the people the closest to Madoff not have an idea what was going on for so long? It's only by studying how Madoff brought people into his web that he understood how the Ponzi scheme began to build.

Nathan Darrow, Robert De Niro and Alessandro Nivola, <em>Wizard of Lies</em>Nathan Darrow, Robert De Niro and Alessandro Nivola, Wizard of Lies

"To me, it's the kind of story that you read into what you want, like a book or a novel or something. As Diana said, you can't label him this or that. That's a danger to go and be too specific in some ways," De Niro said. "He's a classic example of someone who receded very much back and let people come to him. [He] got to a position where people would think its an honor for him to take their money. That's a classic con situation that you see in all forms."

Madoff's victims weren't the only people that he fooled. His wife and son also claimed to have no idea what was going on. Madoff was perhaps the most efficient in throwing off the Security and Exchanges Commission (SEC) for as long as he did.

"We're pretty fair to the SEC because they admit that this is the worst failure in their 75-year history, Henriques says. "There were so many times they attempted an investigation and sometimes they dropped the ball, sometimes Bernie had them wrapped around his little finger, and sometimes they had other business and other scandals that tore them away from this investigation. ... I think you'll see in the movie these aren't bad people, but they are overwhelmed people."

The Wizard of Lies premieres in May on HBO.