LOS ANGELES (CBS) — Fifty years after Marilyn Monroe's death, questions still remain.
"The Kennedys said that they didn't want to see her anymore. It's very easy for someone get away with that back in 1962," said author Jay Margolis, who believes the Kennedys had something to do with her death.
"Marilyn actually overdosed while she was staying here as well," said Hans Weige, referring to Frank Sinatra's Lake Tahoe area lodge and casino -- the Cal Neva.
Did Monroe take her own life or did someone take it for her?
"Marilyn Monroe was murdered," Margolis claimed.
New allegations about Monroe's final hours could rewrite the final scene of her life.
Although she was found dead in the early morning hours of August 5, 1962, in her Brentwood home, there are claims that she spent her final night alive at Frank Sinatra's Cal Neva.
"This is where the rich and elite use to come and this was their private playground," said Weige, tour director of Cal Neva.
Weige showed us bungalow 3, where Monroe often stayed.
A trip Monroe made there five days before her death has been well documented, but according to Monroe's hairstylist George Masters, he accompanied her there the night of August 3rd.
There she reportedly spent time with Sinatra and Mafia boss Sam Giancana, who apparently tried to persuade her one last time not to go public with affairs with JFK and Bobby Kennedy.
Masters claimed that she flew on Sinatra's private jet home to L.A. that morning and was found dead at her Brentwood home that night.
A coroner later ruled that Monroe died from "probable suicide".
"She was found without a bra on and she was known to wear a bra at all times, so that raises a lot of eyebrows on maybe if it wasn't an accident," Weige said.
After her death a host of conspiracy theories emerged, but Masters made his claims in recently-released recordings made a month before his death in 1998.
He recounted two very distinct trips to the infamous lakeside lair, complete with underground tunnels between cabins that would allow another visit by Monroe to go virtually undetected.
"This type of scenario just sounds like nonsense to me," said Margolis, the author of the book Marilyn Monroe: A Case for Murder.
Margolis does not buy the fact that Marilyn was at the Cal Neva the night before she died, but he does agree with Masters when it comes to the Kennedy's being involved in Monroe's demise.
"There was definitely a vast cover-up, as it relates to Marilyn Monroe's death," Margolis said.
They are bold claims, which Margolis says his five years of research and interviews can prove.
Monroe was reportedly found by her doctor nude and lying face down in her bed with sleeping pills nearby.
"There were enough drugs in her to kill about three people, yet there was absolutely nothing in her stomach and that is pretty much the strongest evidence of murder, the fact that there should have been un-dissolved capsules," Margolis argued.
He and others have suggested that Monroe was intentionally drugged, injected with barbiturates, and that Bobby Kennedy visited her hours before she died.
"Robert Kennedy was present at her house along with two men. The housekeeper, Mrs. Murray, was ordered out of the house along with her son-in-law, who was present," Margolis said.
He further claims that Monroe's longtime psychiatrist, Dr. Ralph Greenson, was under pressure from Bobby Kennedy.
"Bobby tricked Greenson into thinking that not only was Marilyn going to reveal the sexual affairs with Jack and Bobby, but Bobby tricked Greenson into thinking that Marilyn Monroe was going to go public with Greenson's affair also, which was not true," Margolis claimed.
Police reports and FBI files on Monroe have been lost, destroyed or blacked out. Her diary was missing from her home.
Her publicist later ended up going to work for the Kennedys.
For many the claims are a step closer to the truth.
But we may never know if her final hours were spent at a rat-pack hangout or her Brentwood hacienda, but her death is still as riveting a mystery as anything Hollywood has ever created.
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