Image copyright Getty Images

When rumours emerged that Aristotle Onassis was romantically involved with Jackie Kennedy, a young Greek journalist sneaked on to the shipping magnate's yacht to see if it was true. Forty years after the death of the billionaire, he remembers how he got his scoop.

On a sweltering morning in August 1968, Greek journalist Nico Mastorakis was in his office in downtown Athens scouring the newspapers for possible leads when something caught his eye.

"I knew that any story about Onassis was big in Greece, even if it was just a photo of him drinking coffee," he says.

He had spotted a small piece reporting that the Greek billionaire had invited Giannis Poulopoulos's bouzouki group to play at a reception on board his yacht Christina. Poulopoulos was a personal friend of Mastorakis.

To add to the excitement, the journalist knew that Jackie Kennedy, the glamorous widow of President John F Kennedy, who'd been assassinated five years earlier, was in Greece. For a while, rumours had been swirling that Kennedy and Onassis were an item. They had been photographed together, but always in company and nothing was known for certain.

Image copyright Nico Mastorakis Image caption Nico Mastorakis

"It clicked in a reporter's mind that I could go myself to Christina disguised as a bouzouki player. I had done that [sort of thing] in the past many times very successfully," says Mastorakis.

Find out more Nico Mastorakis spoke to Witness on BBC World Service Radio

Convinced he had a scoop on his hands, he borrowed a bouzouki and went straight to the airport where he persuaded Poulopoulos to let him pose as a member of the band. They made their way to Onassis's Ionian island, Skorpios, and Mastorakis hid his minute camera behind the strings of his guitar.

Arriving at the Christina, they found Aristotle Onassis in his bathing trunks carefully cleaning the hull of his ship, a former frigate that burned 30 tonnes of oil a day when it was on the move.

Image copyright Thinkstock Image caption Mastorakis hid a small camera in a bouzouki guitar

"Christina at dusk was gleaming with lights. It was a beautiful yacht," he says.

"Everything was mahogany and wood and polished brass. The dinner was served on gold-plated china. Everywhere you turned there was crystal, immense detail.

"It was obviously one of Onassis best-staged evenings of his life. And the purpose of the glamour was that he was in love with the idea of stealing the first lady of the United States."

Crucially, Jackie Kennedy was there. Her brother-in-law, US Senator Ted Kennedy was also on board - to negotiate the financial side of the impending marriage, Mastorakis later learned. Once Jackie Kennedy remarried, she would automatically forfeit the money she got from the Kennedy trust as well as her widow's pension from the government.

"Jackie wore a long gypsy skirt and was very cordial with everybody. They ate lamb and stuffed vine leaves. Onassis tried to feed her and it was a very nice moment," says Mastorakis, who managed to take several pictures.

Image copyright Getty Images

As the evening wore on, Mastorakis watched as the guests became drunk, dancing and singing old tangos. Jackie Kennedy, caught up in the party atmosphere, took one of the costly china plates and threw it to smash it on the deck.

"Onassis grabbed it in mid-air, and asked his staff to bring her some cheap clay plates instead," he says. The tycoon asked Mastorakis to record the singing and happily posed for pictures with the band.

"Jackie drank vodka and Ted Kennedy drank only ouzo but Onassis drank everything. And when he couldn't drink any more, he would go to the side of the boat and empty his stomach in the sea and drink some more," says Mastorakis.

When Jackie eventually went to bed, Onassis stayed on for a bit to drink with the band.

Image copyright Getty Images

"Then he said 'I would love to stay with you until daybreak but I've got to go and make love to my wife.'"

The words confirmed to Mastorakis that the romance was not only real, but serious.

"Onassis wouldn't use random words to describe his feelings. I think he was bragging that after a night of eating and drinking, he was still capable of going to make love to somebody. And the word wife came out with great assurance," he adds.

In addition, Onassis knew Mastorakis was a journalist. He'd run into him in the past as a member of the paparazzi, and even given him a camera as he thought Mastorakis' own one wasn't good enough.

Mastorakis had his story. But there was more. He had also seen Ted Kennedy with an attractive young blonde woman who was not his wife, so he thought he had a double scoop. According to the yacht's head of entertainment, Onassis had had her flown in from Sweden "as a gift" for the senator.

But Ted Kennedy's security detail became suspicious of Mastorakis's good English. The agent was worried that photographs with the Swedish woman could be damaging and he searched the bungalow on the island where the band was staying. Mastorakis realised he needed to get away.

Image copyright Getty Images Image caption Ted Kennedy was a young senator in 1968 with a promising career

The next morning he swapped shirts with another band member and gave the agent the slip.

"As I was flying over the Christina, I spotted the secret service guy on the deck. He looked at me and raised his fist. And I looked at him and I raised my middle finger," he says.

Back in Athens however, Mastorakis was apprehended by the Greek secret police. Ted Kennedy and his agent had leaned on Onassis to pull strings in the military junta that ran Greece at the time.

The journalist spent a night at the police station and when he was released found that both his office and his apartment had been ransacked. All his photographs from on Onassis's yacht had been taken and he never saw them again.

His newspaper published his article detailing the romance between Onassis and Jackie Kennedy. It caused a sensation around the world, but references to Ted Kennedy had been removed.

Image copyright Getty Images Image caption Jackie Kennedy and Aristotle Onassis married on Skorpios later that year

"It was reprinted by thousands of newspapers and magazines. The headline ran: 'Ex-first lady of the United States, soon to be first lady of Skorpios.'"

Jackie Kennedy married Aristotle Onassis on the island that October, but seven years on she found herself a widow again, when the Greek magnate died after a short illness.

Mastorakis went on to write a film script based on his encounters with Onassis and today hosts a Greek TV-programme interviewing celebrities.

Nico Mastorakis spoke to Witness on the BBC World Service.

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