Sir Trevor McDonald's latest documentary sees him rubbing shoulders with members of the mafia, but meeting mobsters was nothing compared to reading the news for the first time.
"I was wetting myself with anxiety over that one!" confesses the veteran news broadcaster, laughing.
McDonald, who was knighted in 1999 for services to journalism and received the Bafta Fellowship in 2011, has seen and heard a fair few things in his time, and it takes a lot to shock him.
But he admits he was left speechless when interviewing Michael Franzese, one of history's most successful mafia men, for the new two-part series.
In the Seventies and Eighties, Franzese posed as a major Hollywood film producer so he could launder large amounts of stolen money, and at one point in the documentary, reveals he was making $10m dollars a week.
"That did make my face tweak," admits 75-year-old McDonald, who spent three months travelling across the United States as he sought access to the secretive world of the Cosa Nostra.
Franzese was finally indicted, but struck a deal with the FBI and served seven years in prison. He's now turned his back on the organisation, but his past haunts him.
"All these horrible memories," explains McDonald, who's fronted numerous documentaries, including a series on death row inmates, in which he spoke to some of America's most notorious criminals. "One of his problems is that a lot of the people he ratted on don't believe the money's just disappeared."
Another guy he meets is John Alite, known as "The Sheriff", who grew up in New York. In the Eighties and Nineties, he worked for John Gotti Senior, the Godfather of the notorious Gambino crime family, and rose through the ranks by carrying out brutal orders.
"You thought you knew what stories about the mafia would be like, but confronted by the reality of what these people were telling you, it was much more extraordinary than you could've dreamed of. And the bluntness was amazing," adds McDonald, who retired from presenting the ITV news in 2008.
"Journalistically [you think], 'Wow, thanks for telling me this', but it's absolutely shocking, the number of people they've killed."
It isn't a world that exists solely in the past, either, and McDonald witnessed the "clear and present danger" when driving around New York's Little Italy with Michael Di Leonardo, nicknamed Mikey Scars.
A former high-ranking member of the Gambino crime family, who testified against the men he worked with to save himself from a life behind bars, he now lives in permanent fear of a revenge attack - and that fear is evident when he spots two mafia members at a roadside bar.
"It was the only moment where I thought I'm in the wrong place at the wrong time," admits McDonald. "I was scared by the fact that he was scared. He's a hard man and, if he's worried, then I suspect you should be, too."
Given the mafia live by a code of secrecy, McDonald credits the series producer and his team for achieving unprecedented access. "By the time I got there, I had the easy job of asking the questions," he says. "If I may make one boast about myself, I spend an enormous amount of time thinking how to structure these interviews to get people to just talk.
"One of the keys is a non-judgmental approach. The people in prison and the mafia, they have done what they have done and probably been convicted and paid a certain price for it. It's not for me to inflict my own judgments.
"You just want them to tell you about their lives, so you don't have to shout at them. That might be counter-productive. Or they might punch you."
Plus, people enjoy talking about themselves, he says. "We all have a touch of ego about life, and it's terribly nice for people to ask you what you've been doing, although [in this instance], what you've been doing is killing people."
Some of the participants have watched previews of the series. "I must confess, I was rather wary when I heard we were going to show them, but they loved it. For me, it's the integrity for which we do our stuff. There's nothing underhand about it."
McDonald has only watched it once. "I am a great, great critic of what I do and I always look back and think, 'Gosh, I could've said something differently'," he reveals. "But there's not much I would change with this."