Aristotle Onassis and Maria Callas.Photo:Hulton-Deutsch Collection/CORBIS/Corbis via Getty

Hulton-Deutsch Collection/CORBIS/Corbis via Getty
When Aristotle Onassis, the Greek shipping magnate, metMaria Callas, the great opera diva, in 1957 they were both married to others. But that didn’t stop them from falling in love andhaving an affair that would last until his deathin 1975.
“They couldn’t live without the other one,” Kiki Feroudi Moutsatsos, Onassis’ longtime personal secretary, tells PEOPLE.
Once their affair began, she says, they “never stopped seeing each other — never.” Even after he divorced his first wife and later marriedJacqueline Kennedyin 1968.
“Onassis was protecting his affair,” recalls Moutsatsos, 75. “He was protecting Jackie, but Jackie was very smart. Everyone in the house was speaking, secretly, of course, that Onassis every night was visiting Maria. She knew. She was discussing it with Onassis' sister, Artemis. She was complaining. Artemis told her not to fight. Just ignore it.”
“Not that it would have been changed,” she adds.
Aristotle Onassis and Maria Callas on June 24, 1959.Evening Standard/Hulton Archive/Getty

Evening Standard/Hulton Archive/Getty
Few were as close to what really happened as Moutsatsos, who began working for Onassis when she was 17 and later wrote the 1998memoirThe Onassis Womenthat she is looking to republish.
“They often saw each other in Paris,” Moutsatsos recalls. “Their houses were very close.” Onassis had an apartment on Avenue Foch and Callas lived at 36 Avenue George Mandel, both in the posh 16th arrondissement.
As she recounts, “When I was calling every morning, in Athens or in Paris, and I was speaking with the personnel, and they were making jokes, they were telling me Mr. Onassis was very, very tired. And when I was asking why, they were saying again that Maria was visiting.”
Maria Callas and Aristotle Onassis.Getty Images

Getty Images
“We knew every moment what they were doing,” says Moutsatsos of all the women in Onassis’ life. “Because I was arranging from my office and could make all the details about the trips. Christina [Onassis’ daughter] and Jackie called me to tell me when they would be in Paris and when in the United States.”But Callas wasn’t always happy with her lover. Says Moutsatsos, “When she was on the boat (Onassis’ yacht, theChristina) she was reading the newspapers and seeing all the rumors — and scandals — about Aristo; they were fighting.”
Jackie Kennedy and Aristotle Onassis.Bettmann Archive

Bettmann Archive
“He liked to have next to him beautiful women, and Maria was very jealous,” recalls Moutsatsos, who’s memoir is the basis for a short filmThe Heiress, now screening on the festival circuit. “She was very nervous. When articles in the newspaper or magazines appeared, she couldn’t stand it. She was always fighting with him.”
Jackie, on the other hand, rarely showed her emotions. Their marriage grew increasingly rocky in later years as they spent time apart. Still Onassis continued to see Callas.
The opera singer never truly recovered after his death on March 15, 1975. Afterward, Moutsatsos recalls, “Maria was desperate. She didn’t want to live anymore.”
As for her own turn as the dramatic opera star, Oscar-winner Jolie has said, “I hope what audiences find is that there was so much research done into what we believe she really was like — the human being behind the voice and behind the image. Maybe not ‘behind the voice,’ because the voice is the woman,” she toldThe Hollywood Reporter.
Angelina Jolie and Pablo Larrain on the set of “Maria”.Pax Jolie-Pitt/Netflix

Pax Jolie-Pitt/Netflix
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“But I think even if I’d read biographies on her, I [wouldn’t have understood her] until I stepped in and kind of felt her. I hope more people discover her and opera and go to the opera and listen to opera.”
Mariais in select theaters now, then streaming on Netflix Dec. 11.
source: people.com