Marilyn Monroe's death did not happen immediately when she was found, a new documentary revealed.

Years after Monroe's death, the event is still being surrounded by bombshell details and mysteries. The theories about her passing emerged again before the release of a new Netflix documentary.

On Wednesday, the public will be able to know more truths about Monroe through the documentary, "The Mystery of Marilyn Monroe: The Unheard Tapes."

Initial reports revealed that her housekeeper found the actress' nude, lifeless body at her Brentwood, California, estate on Aug. 5. 1962, at around 3:00 a.m. It was revealed that she died one hour before the police arrived on the scene, seeing several bottles of sleeping pills around her.

However, the documentary will offer a hair-raising truth.

In the documentary's trailer, ambulance company owner Walter Schaefer revealed that Monroe was still alive when she was found at her home. One of her former drivers, Ken Hunter, was still able to drive the actress on the night of her death.

According to Schaefer, Monroe was comatose - but alive - when the driver picked her up and drove her to a medical facility's emergency room.

This supported what writer John Sherlock's claims, saying that Monroe's psychiatrist, Dr. Ralph Greenson, told him that the actress was still alive at home. However, she died en route to Saint John's Health Center.

"She died in the ambulance. Then they took her back to the house. [Greenson] told me he was in the ambulance," Sherlock said in the documentary.

Was Marilyn Monroe Murdered?

Authorities announced nothing but claims about Monroe's death, saying that she died due to a barbiturate overdose in 1962.

However, Monroe's close friend, Frank Sinatra, reportedly believed that she was murdered.

In film producer Tony Oppedisano's Sinatra memoir, "Sinatra and Me: In The Wee Small Hours," he dropped shocking details about the singer's beliefs.

Before the crooner died in 1998, he reportedly revealed that Monroe was instead murdered. Due to the misleading investigations, the 82-year-old singer never really got over her death.

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According to the film producer, Monroe spent time with her ex-husband Joe DiMaggio at the Cal Neva Lodge near Lake Tahoe. The place was partially owned by Sinatra.

After the meetup, she decided to release a statement about her decision to reconcile with DiMaggio. As the press conference's news spread, people alleged that the model would announce details about her relationships with former President John F. Kennedy and his brother Robert F. Kennedy.

As Monroe planned to share details about the Kennedys, she was reportedly murdered as a result. For Sinatra, he believed that his friend would still be alive if she never announced the press conference.

Sinatra's attorney Mickey Rudin then delivered the death news days after. There was a rumor about the involvement of Mob Boss Sam Giancana's men.

"She'd been murdered with a Nembutal suppository and Robert Kennedy or the Mob was involved," Sinatra said, per Oppedisano.

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