Marilyn Monroe
How or what killed Marilyn Monroe at the age of 36? Skyhouse Publishing

Sex symbol Marilyn Monroe died August 5, 1962 in the bedroom of her Brentwood, Los Angeles, home. The actress was found dead by housekeeper Eunice Murray, who called Monroe’s psychiatrist, Ralph Greenson, before alerting authorities. She was 36 years old at the time of her death.

The corner ruled Monroe overdosed on barbiturates (nervous system depressants), but not everyone believes that. There are several conspiracy theories about Monroe’s tragic death. Some of the most popular ones have been listed below.

1. Suicide

This is the lesser-believed theory. It was rumored that Monroe was distressed several weeks before she died. She was found face down with sleeping pill bottles strategically arranged near her bed.

The coroner’s finding stated: “Miss Monroe has suffered from psychiatric disturbance for a long time. On more than one occasion … when disappointed or depressed, she has made a suicide attempt. On these occasions, she had been rescued. It is our opinion the same pattern was repeated [on August 4] except for the rescue.”

Again, not everyone is so sure-- including one of the actresses who played her. The new Lifetime mini-series, “The Secret Life of Marilyn Monroe,” makes it seem as if Monroe was in and out of mental hospitals. Actress Kelli Garner, who plays the sex symbol in the film, said it’s like “historical fiction,” during an interview with FoxNews.com.

"I have heard so many different things," Garner said. "I don't want to think that she killed herself. That's a hard one for me. That one makes me sad."

2. Accidental Overdose

It was all just a tragic accident. Monroe’s death wasn’t the first time she had overdosed, the U.K.’s Metro reported. It had happened “many times” before her untimely death.

3. Murder

This is the most popular one. An overwhelming amount of conspiracy theorists believe the Kennedys murdered Monroe, or that the Kennedys at least had a hand in her death. Monroe supposedly had affairs with President John F. Kennedy and then his brother Robert F. Kennedy after the president passed her along to him.

In the book “The Murder of Marilyn Monroe: Case Closed,” written by investigative reporter Jay Margolis and New York Times best-selling author Richard Buskin, the alleged murder of Monroe was orchestrated by RFK and co-conspirators like brother-in-law and actor Peter Lawford, after the actress threatened to air dirty political secrets they had disclosed to her.

“Bobby Kennedy was determined to shut her up, regardless of the consequences," Peter Lawford said after her death, according to the authors. “It was the craziest thing he ever did-- and I was crazy enough to let it happen.” Lawford apparently felt guilty after her death, which is when he made this statement, the U.K.’s Daily Mail wrote.

The murder supposedly was conducted by giving her a lethal injection via enema. Traces of pills were not found in her stomach during the autopsy and nothing to drink the pills with was discovered in the room either. There also wasn’t any vomit, which is usually what happens when a person overdoses.

The mafia comes into play for several reasons, Metro noted. They either wanted to frame the Kennedys to make it look like they were the ones guilty or the mafia murdered her for the Kennedys.

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