'I look decent considering, right?" Jordan Belfort asks me. "I should look like Keith Richards from the Rolling Stones. I have never had my hair dyed, I've never had plastic surgery. I can find a few greys in there so you can see."
The 51-year-old dips his head forward flirtatiously so I can take a closer look. He's right: he doesn't have many greys, and he deserves to look considerably more haggard. Belfort is the real-life Wolf of Wall Street, the crooked stockbroker who inspired Martin Scorsese's new film of the same name, and whose excessive lifestyle makes even Gordon Gekko, the fictional villain in the 1987 film Wall Street look restrained. As the founder of Stratton Oakmont, a New York stockbroking firm, Belfort defrauded investors of more than $100 million (pounds 60 million). He smuggled a fortune to Switzerland, roping family members into the plot and putting them in danger of imprisonment. Meanwhile, he staged midget-throwing contests in the office, entertained prostitutes by the dozen, and spent years high on cocaine, crack, Quaaludes (sedatives) and Ecstasy.
While he was under the influence, he also sexually assaulted an air hostess, pushed his then wife down the stairs, and strapped his young daughter into a car that he promptly drove through a garage door. Belfort got away with breaking the law for years because he had enough money, influence and loyal acolytes to negotiate his way out of trouble. But when the authorities finally caught up with him, he also broke the code of honour among thieves. He agreed to turn in his friends in order to save his own skin. And yet, somehow, this morally bankrupt thief is now hailed as something of a hero. On a sunny afternoon in Los Angeles, Belfort claims his story serves as a "cautionary tale".
But, in Scorsese's hands, it is a riotous celebration of Wall Street success. Yards from Goldman Sachs's headquarters in downtown Manhattan, bankers invited to a preview of the film cheered Belfort's every move. They laughed as the Wolf - Leonard DiCaprio in an Oscar-nominated turn - snorted drugs from a prostitute's naked body, and applauded when he ripped open a sofa to find a stash of cocaine. The only evidence of moral disapprobation came when the character took a swing at his wife. In London, City firms have attended fancy-dress screenings, with staff posing as their new folk hero, complete with pastel-coloured jackets and brick-like mobile phones. Cinemas have trebled the price for private bookings, such is demand.
All this brash hero-worship is deeply distasteful, especially given the havoc bankers' greed has wreaked on the economy. I expect to thoroughly dislike Belfort, but I find myself reluctantly charmed. It is no accident. Belfort, who makes a cameo appearance in Mr Scorsese's film as a conference compere, uses the same techniques to win approval as he would to close a deal. He coaxes his audience into a series of calculated "microagreements", to create an "atmosphere of complicity", and then slowly reels them in. "You seem like a really, really nice person," he says, when I ask him if he feels guilty. He speaks with a strong Brooklyn accent, fixing me with clear blue eyes. He is shorter than expected, but pleasant-looking, cutting a preppy figure in blazer and jeans. "I want to give you a good answer here that will hopefully be a bit special."
Obviously I am being played, but that doesn't mean it doesn't work. And he's a master of the art. After a spell in prison - he served 22 months of a four-year sentence - Belfort reinvented himself as a motivational speaker, and looks back on his own wild ways with "disbelief". "If I could do it again, I'd definitely take a completely different path," he says. Yet minutes later, he tells me: "If I could have done this and not lost all the money, I wouldn't change a thing." He enjoys telling the stories of his worst excesses, and chuckles as he recounts the time his 170ft yacht was destroyed because he forced his captain to take it out in a gale-force storm. "It was a bad dose of Quaaludes that led me to have these ants in my pants. I couldn't bear sitting in the harbour for one more moment. But what a great thing that happened for the movie!" he says. Three people died when the plane coming to rescue him crashed. Later, he insists that he is no Bernie Madoff, the US stockbroker sentenced to 150 years' in jail for fraud.
"It was wrong, [but] I wasn't dealing with poor people. I was dealing with very rich people. No one lost their life savings." Basking in the sunshine in California, where Belfort now claims to lead a squeaky-clean life, it is easy to believe he is just a lovable rogue. But a wolf in sheep's clothing is still very much a wolf at heart.