When Monroe appeared to sing “Happy Birthday, Mr President” to JFK in 1962, his brother-in-law Peter Lawford announced her as “the late Marilyn Monroe”. Three weeks later, she was dead. Earlier that year, she had bought a hacienda in LA with the words “Cursum Perficio” engraved on a flagstone: Latin for “I have run the course”.

Monroe had been planning to make a biopic of her childhood obsession, Jean Harlow, Hollywood’s original peroxide sex symbol, who – like her – loved disastrous men, was better than the movies she was in, fought the studio system, and had a complicated mother. “I kept thinking of her, rolling over the facts of her life in my mind,” she said. “It was kind of spooky, and sometimes I thought, ‘Am I making this happen?’ But I don’t think so. We just seemed to have the same spirit or something, I don’t know. I kept wondering if I would die young like her too.” Harlow was dead at 26, of kidney failure, after endless shots of sedatives by the studio doctor.

The unembroidered facts of Monroe’s life – spawn of Hollywood, doomed to be Harlow – already feel like a novel, full of clunky foreshadowing. No wonder that, decades later, Miller told Oates everything that had been written about Monroe was a kind of fiction. Her story attracts it, even before all the unreliable and conflicting testimonies – people claiming to have been her best friend, or even her secret husband – that since her death have accrued like barnacles on a sunken wreck.
People want to insert themselves into Monroe’s story, to own a piece of her, because she feels like America’s closest equivalent to a Greek myth. Her sphinx-like smile has become shorthand for all that was delightful and all that was shameful about 20th-century America. 

And we can’t let her go. A new Netflix documentary, out on Wednesday, picks over the convoluted mystery of Monroe’s death, this time through little-heard tapes from her inner circle. In Oates’s novel, Monroe takes an accidental overdose – but there follows a scene where “the Sharpshooter” from “the Agency” comes to deliver a lethal dose of nembutal in a hypodermic, and clear her house of written “materials”. Does Oates share the view that Monroe was killed – because of the Kennedies, because of the Mafia, or both?

“That could be something like a hallucination,” she tells me. “But I also wanted to leave the possibility – like an alternative universe. It’s quite possible – not probable, but possible – that she was assassinated.” It’s more probable that “she might have been allowed to die” after telephoning for help. Oates points out that Monroe’s house had been cleaned out, and her telephone records expunged before the LAPD arrived at the scene. “They came after some other law enforcement – probably the FBI.”

Either way, Monroe “would have probably tried to commit suicide at some other time. She was sort of doomed. She was in a kind of tunnel.” In the end, says Oates, “glamour killed her.”

Read Joyce Carol Oates’s short story, ‘Miss Golden Dreams 1949’, here. ‘Night, Neon and Other Stories of Suspense’ (Apollo Fiction, £18.99) is out now. ‘The Mystery of Marilyn Monroe: The Unheard Tapes’ is on Netflix from Wednesday.  The film of ‘Blonde’ is out later this year