Frank Sinatra believed his 'close friend' Marilyn Monroe was murdered, reveals new book

A new book written by Frank Sinatra's former manager Tony Oppedisano has revealed that he believed Marilyn Monroe was murdered.

In his memoir "Sinatra and Me: In The Wee Small Hours," Oppedisano writes that the late musician spent the later years of his life reminiscing about his loves, his losses, and the friends he missed most, including Marilyn Monroe. According to the book, Sinatra never believed that Monroe's death was caused by an overdose, and would repeatedly say that she was murdered, reports People.

Monroe, who struggled with mental illness and substance abuse for several years, was found dead at her 12305 Fifth Helena Drive home in Los Angeles, California in August 1962, at the mere age of 36. The Los Angeles County coroner's office ruled that her death, caused by a barbiturate overdose, was a probable suicide. The report mentioned the precedents of her overdosing and being prone to mood swings and suicidal ideation, while noting that the large amount of drugs she had ingested indicates it wasn't an accidental overdose.

Although the coroner's findings ruled out any foul play, several conspiracy theories cropped up suggesting murder or accidental overdose, some of which even blamed then US President John F. Kennedy and his brother, Robert, as well as union leader Jimmy Hoffa and mob boss Sam Giancana. The case was reviewed two decades later in 1982, but no evidence was found to support the theories.

However, Sinatra was one of the many people who believed that his friend was killed. Oppedisano writes in his book: "Frank believed she was murdered and he never got over it."

About Sinatra's relationship with the actress, Oppedisano wrote that they were close friends but not lovers. The musician found Monroe beautiful and funny, but "too troubled, too fragile, for him to sleep with and then walk away." However, she did confide in the musician about her intimate secrets including her affairs with the Kennedy brothers, telling him she doesn't understand "why they'd shut her out completely once she stopped having sex with them."

The weekend before her death, the actress spent time at the famous Cal Neva Lodge which was partially owned by Sinatra. Unknown to the world, she was there to meet her ex-husband Joe DiMaggio who was staying nearby and had decided to make a press announcement the following week about them rekindling their romance, claims Oppedisano.

However, the announcement of the press conference sparked rumours that the actress was planning to spill the beans about the Kennedys, which according to Sinatra she would have never done because she still had feelings for Jack.

"Frank believed if the press conference hadn't been announced, she would have lived a lot longer," Oppedisano writes, adding that the actor was told by several sources that she was "murdered with a Nembutal suppository and Robert Kennedy or the Mob was involved."