What to Know About the Real Maria Callas, the Soprano Played by Angelina Jolie in Netflix’s Maria

Maria Callas (1923-1977) is often hailed as one of the greatest sopranos of the 20th century. She’s best known for her performances in the operas Medea, Tosca and La Traviata, and when TIME put her on the cover of the Oct. 29, 1956, issue, the magazine dubbed her “the undisputed queen of the world’s opera.”

But Maria, the Netflix biopic starring Angelina Jolie as Callas out today (Dec.11) does not take place at the height of her career. Rather, it takes place at the lowest point. Set in the last week of Callas’s life, she’s living in Paris and doing a lot of looking back because she feels like she has nothing to look forward to.

A biopic examining her life would perhaps be a dream come true for the New York-born singer, given she loved to be the center of attention, according to Callas's biographers. But the film doesn’t glamorize Callas, and instead portrays her as sad and withdrawn. TIME explored why she was in a very dark place at the end of her life.

Callas’s mental health

Callas was known for having a big ego. In one scene she proclaims, “I come to restaurants to be adored.” She tells everyone she’s writing an autobiography and an aria—neither of which she did in real life.

At her performances, she tended to create a scene. “She was known for leaning over and shaking her fist when people were hissing or booing,” says Lyndsy Spence, author of Cast a Diva: The Hidden Life of Maria Callas. She had a terrible temper, and there are plenty of scenes in Maria where her character has little patience with people.

Throughout the movie, Callas hallucinates that TV cameras are follow her, and behaves as if she is being interviewed although no one is there. In the film, she’s periodically popping Mandrax, a highly addictive sedative that can cause hallucinations, and she was indeed addicted to the drug in real life.

After talking to the daughter of Callas’s neurologist, Spence believes the singer may have had a neurological condition on the multiple sclerosis spectrum. Toward the end of her life, Callas “physically can't command her voice and get the strength to sing, and that obviously builds up to a point where she can no longer live with it,” Spence says. “In the late 1970s, she started to self medicate to try and ease the symptoms, and unfortunately, became addicted to prescription drugs, one of which is Mandrax.”

Paul Wink, a professor of psychology at Wellesley College and author of Prima Donna: The Psychology of Maria Callas, argues that she would probably be diagnosed today with depression and drug addiction. “She died addicted and in despair,” he says.

Callas and Aristotle Onassis

Callas’s relationship with Aristotle Onassis, the Greek shipping mogul, could be the plot line of an opera. He actually hated opera, but loved the scene and the glamour of it all.

“What he liked was the party afterwards, when he and she would be the center of attention backstage,” says John Louis DiGaetani, author of The Definitive Diva: The Life and Career of Maria Callas.

Callas wanted him to marry her, but he left her for Jacquline Kennedy, the widow of slain President John F. Kennedy. As the movie shows, Callas really did find out by watching television news in Paris.

“He’s a collector of rich and famous women,” Spence says.

Callas was rumored to be pregnant with Onassis’s child at one point. The biographers that TIME spoke to say there is no proof that that was the case, but that if she carried anyone’s child, it would be Onassis’s.

In the movie, Callas is told, “Jackie was his wife but you were his life.” The marriage between Onassis and Kennedy was not a happy one. By the time Onassis realized Callas was the love of his life, it was too late to rekindle their relationship. He died in 1975. Callas never recovered from that loss.

Callas at the end of her life

Callas was “lonely, disillusioned, basically fed up,” as Spence describes the singer in her final days.

In the movie, as in real life, she spent most of her time playing cards with her butler and her maid and tending to her dogs.

She was estranged from her family. Her mother was a stage mom who pushed her into the opera, desperate to make money off of her daughter’s voice. In one scene in the movie, her mother asks her for money, and there’s some truth in that. According to Spence, her father once pretended he was dying of cancer and needed her help paying his medical bills.

She struggled to find purpose in her life beyond the opera. “When she developed a relationship with Onassis, opera was no longer her life—Onassis was her life,” Wink says. “It would have been nice for her to find her own sense of identity, but she couldn't do it. That's why she was living in despair. That's why she was taking Mandrax and became a recluse.” 

Callas was found dead in her Paris apartment at the age of 53. The cause of death was a heart attack.