Robert De Niro may play the role of Bernie Madoff, the man behind the biggest stock-market fraud in history in HBO's The Wizard of Lies, but that doesn't mean he understands him.

"What he did is beyond my comprehension," says the Oscar-winning actor, who has played his share of criminals.

The HBO TV film, which will be broadcast in May, features Michelle Pfeiffer as Madoff's wife, Ruth, and is helmed by Barry Levinson, the Oscar-winning director behind Rain Man, Bugsy and Good Morning, Vietnam.

For nearly 20 years, Madoff, now 78, was a Wall Street superstar. He orchestrated the huge pyramid scheme that fraudulently took in anywhere between $23 billion and $65 billion.

He never actually invested even a penny of the sums his clients entrusted to him, instead drawing on funds from new investors to remunerate the older ones.

But the house of cards collapsed in December 2008 when a growing number of investors, panicked by the financial crisis, attempted to cash out their investments.

Madoff is now serving a 150-year prison term.

Having grown up in modest circumstances in the New York borough of Queens, Madoff "must have had some kind of very strong disdain" for the people he was swindling, De Niro believes. "He wanted to be part of that world, but he wasn't."

De Niro, who says he found there to be "a disconnect somehow" in Madoff, believes his wife and children probably had suspicions as to his illicit activities.

His clients, as well, may have had doubts in the face of the staggeringly high returns he offered. But as long as the money continued to pour in, they were not about to look any further.

The film is based on a book by journalist Diana Henriques, The Wizard of Lies: Bernie Madoff and the Death of Trust.

"All of us trust people in our lives, and only someone you can trust can truly betray you," the financial journalist said.

Henriques says De Niro's performance showed "how plausible con men like this are, how utterly they can seize your trust and your imagination and make you believe."

New York-born De Niro, already the winner of two Oscars, is soon to begin filming the next Martin Scorsese film, The Irishman, playing the title role of a notorious mobster.

The fall of Madoff has been brought to the screen before, notably in the ABC miniseries Madoff.