On the day that Jacqueline Bouvier Kennedy married the shipping magnate Aristotle Onassis in 1968, New York was appalled.

“To us, she was royalty, a princess, and I think she should have married a prince, or at least someone who looked like a prince,” a retired book-keeper told The New York Times. A secretary from Brooklyn said that it was all anyone could talk about in her office. An air force pilot said that he personally had been “pulling for the prime minister of Canada”, Pierre Trudeau, who was then single and by all accounts quite a catch. The mood was summed up by a headline: “Jackie, how could you?”

No one seems to have asked the same question about Onassis, or wondered at his reasons for making the match. Now they may hear his side of the story.

Onassis will come before them in the form of a fellow from south London who happens to look like him.

Anthony Skordi, an actor last seen on British screens in the prequel series Prime Suspect 1973, was informed of his resemblance to the shipping magnate while shooting a film with a soap actor named Thaao Penghlis. “He said, ‘You look like Onassis’,” says Skordi. “I was highly offended. Did you ever see the headlines for his marriage to Jackie Kennedy? It was like: ‘Beauty and the Beast’, ‘Toad Marries Princess’ … ” He trails off. “He was short,” he adds.

But after the film shoot wrapped and he was back home in Los Angeles, he started reading biographies.

“I read a total of ten,” he says. The story began to take hold of him. “He was raised in Asia Minor, in Smyrna. The place was decimated in 1922, it was burnt down [following its capture by the Turkish army]. It takes a special kind of person to kick away from that. While a lot of people would have harped on about it for the rest of their lives and been miserable, he started an empire.”

The mood was summed up by a headline: “Jackie, how could you?”

Onassis made his first fortune in Buenos Aires, and then several more. “He owned half of Monaco, he owned 30 companies, he owned a national airline. He had 128 ships and he knew exactly where they were at any given moment.” Plus, of course, “he married the [former] first lady of the United States and had mistresses, including Greta Garbo, all these different women”.

Skordi wrote a one-man play, Onassis, which opened in New York this week. The conceit was: “What would Onassis say, if you were in his living room? How would he describe his life?” Occasionally, as he talks about the play, he drops into his character’s voice. He does Onassis complaining about his new wife’s monthly clothing allowance: at least $20,000 a month. And yet he only saw her in jeans. “I know what she does with the clothes she buys,” he says. “She resells them. Before she even wears them. She launders the money!” Apparently this is true, Skordi says. She really did sell her allowance-bought clothes, still in their packaging.

Sometimes, in the play, he directly addresses members of the audience as Onassis, hoping for their indulgence. Occasionally he worries about how they will take to the man. In the play, describing his many passionate entanglements, he declares: “Love-making is always better after a struggle, and a slap or two.” Then, if the crowd seems concerned, he sometimes adds: “But you must have a safe word.”

Onassis is on at the American Theatre of Actors, in New York, through March 20

Will Pavia is the New York correspondent for The Times of London