Marilyn's last day: Twenty-four hours inthe death of a legend

Marilyn Monroe woke early that Saturday morning. She had slept badly. She surveyed herself in the mirror - thinner than she had been in years, she looked tired. She needed a manicure and a pedicure. But first, feeling the old anxieties crowding in, she needed to talk. Who should she call? One of her three ex-husbands? Her psychiatrist? The White House?

As befits a Hollywood legend, the last day of Marilyn Monroe's life is shrouded in mystery. The 36-year-old actress spent Saturday 4 August 1962 at her Los Angeles home. By early next day she would be dead, found nude by her housekeeper, face down on her bed, clutching a telephone receiver, an empty bottle of Nembutal capsules at her side. When news of her apparent suicide broke the next day, America was astonished that the star had been without a date on Saturday night.

Forty-four years after her death, and the details of what happened during those hours are less clear than ever. Was it suicide or murder? Was Monroe driven to despair by the recent end of her love affair with President Kennedy? Only two months earlier she had sung "Happy Birthday, Mr President" at Madison Square Garden, but he ended the relationship brutally soon after. Had she embarked on a new relationship with his brother Robert F Kennedy? Marilyn was known to keep a little black book documenting all her affairs and conversations. At the time of her death, Hollywood rumours were circulating that she was about to announce a press conference the following Monday.

The coroner's official verdict was "probable suicide". Monroe was represented as a professionally unreliable, pill-popping depressive. Always highly strung - she suffered rashes, hysteria, sickness and other psychosomatic illnesses which could be triggered by tension or confrontation - her critics argued she had simply spiralled into self-destruction. Terrified of abandonment (as a child she was shuttled between orphanages and foster parents), she feared turning into her mother, who had spent most of her life in a psychiatric clinic. A year previously, suffering from depression, Monroe had checked into the Payne Whitney psychiatric clinic. To her horror she was locked in a padded cell. It was only when she phoned her ex-husband, baseball star Joe DiMaggio, that she was released.

That August day, Monroe, her critics argued, was an ageing sexpot with a washed-up career. Pale, thin and lifeless, her hair ruined by bleach, she wouldn't leave the house without her make-up man and hairdresser to prepare her. She had been fired by Fox and replaced on her last film, Something's Got To Give (the studio claimed she had cost them $2m in delays). Her love life was in pieces, with the end of her marriage to the playwright Arthur Miller. She was embarrassingly promiscuous, there were rumours of an abortion. No wonder she killed herself.

Others, however, insist Monroe had never been happier. Decamping from New York to Los Angeles represented a fresh start. She had bought her first house and was refurbishing it. Yes, she was self-medicating too much and receiving psychoanalysis to cope with the end of her marriage, but in the week before her death, her career was back on track. She was the cover star of both Life and Paris-Match. After seeing the triumphant rushes of Something's Got To Give, Fox had rehired her - she was due to report for work again on Monday. Her 23 movies had grossed more than $250m.

Which image is true? Every year, it seems, a new piece of the jigsaw emerges. In 2004, alleged transcripts of tapes that Monroe made for her psychiatrist, and gave to him the day she died, were published, revealing her to be far from suicidal. Last week a letter written by Monroe to her acting teacher, Lee Strasberg, was made public. Although composed eight months before she died, it details Monroe's plan to set up an independent film production company with Marlon Brando.

When it comes to Monroe, the conspiracy theorists are listened to. Next Saturday, the Barbican is celebrating the 80th anniversary of Monroe's birth in 1926. The event will be introduced by Sandra Shevey, the first biographer to argue definitively that Monroe was murdered.

As with Diana, Princess of Wales, every detail of Marilyn's last days have been picked over. The fascinating thing about Monroe's death is that potentially everything - and nothing - is true. Even the time of death is disputed. Monroe's doctor called the police to register it at 4.25am on Sunday 5 August, but there is evidence that she died around eight hours earlier. The coroner's report stated that Monroe's death was due to a massive overdose of 47 Nembutal capsules but there was no trace of drugs in her stomach, or evidence of her having taken the tablets orally. Later, Sgt Jack Clemmons of the LAPD claimed that it looked as if her body had been posed on the bed, legs stretched out perfectly straight, unlike the contorted bodies of most victims who have overdosed on sleeping tablets.

Key forensic evidence went missing shortly after she died. All the key witnesses from that night (police, friends, a psychiatrist, an attorney, her press agent) contradict each other, and several have changed their stories. So what exactly happened on that fateful Saturday?

Monroe's agent, Pat Newcomb, stayed over on the Friday. She says that the actress woke up feeling cranky through lack of sleep, but was excited about a delivery of furniture from Mexico. When her housekeeper, Eunice Murray, arrived at 8.30am, she claimed Monroe was already up, tiling the floor.

Newcomb awoke at noon, and she and Monroe argued, apparently over Newcomb's ability to sleep in, but it was soon resolved. Pat says they planned to sunbathe by Monroe's pool, then maybe join the actor Peter Lawford and his wife Pat (a Kennedy sister) for supper.

Some time during Saturday morning, Monroe's mood changed. She was unsettled by the arrival of a stuffed toy in the post with no note. There was a flurry of phone calls. Murray recalls Monroe asking if they kept oxygen in the house, an odd request. Shevey believes that Monroe had begun to fear for her life, aware that she was a political liability. "John F Kennedy was going to run for a second term, Jackie had to be happy with all of it. They needed Marilyn out of the picture."

Newcomb went out shopping, and said Monroe was upbeat when she returned. But her psychiatrist, Dr Ralph Greenson, who had arrived for his daily visit, claims Marilyn was in a highly emotional condition.

Greenson asked Newcomb to leave, and then asked Murray to stay overnight with Marilyn. He left at 7pm. Marilyn took the phone into her bedroom and Murray claims she never saw her alive again. Lawford says he rang Monroe at 7.30pm and she sounded depressed and slurred. He claims she said, "Say goodbye to the President and say goodbye to yourself, because you're a nice guy," before her voice faded out. However, his view is contradicted by Joe DiMaggio Jnr, the son of her second husband, who says he phoned her at 7.30pm to tell her he was breaking off an engagement she disapproved of. He says Monroe was in a very good mood at the news.

Later that night, Monroe was found dead. Murray woke up and claims she saw a light under the door. Concerned that something terrible had happened, she called Greenson at 3.30am. They peered into Monroe's bedroom window and saw her naked body. Greenson says he broke in with a poker, before ringing Marilyn's physician, Dr Hyman Engelberg, but the window had been mended by the time the police arrived.

All these details have been challenged over the years, and it is undoubtedly true that Murray was an unreliable witness. That August, Monroe had fired her. Her last contracted day of work was Saturday 4 August, 1962. In 1985, after years of denying it, Murray admitted during a BBC interview that Robert Kennedy had visited Monroe's home that day; a claim backed up in 1993 by Murray's brother-in-law who worked as Monroe's handyman. Murray also let slip that an ambulance had arrived while Monroe was still alive.

No one knows exactly how many people had access to the house the night Monroe's body was found. Papers were destroyed, telephone records seized. Were they searching for that little black book?

Sydney Guilaroff, her hairdresser, says Monroe called him twice, quite hysterical, to say that Kennedy had been at her house with Lawford threatening her. The last phone call Monroe made was to the White House. Was she calling JFK? There are even rumours that she spoke to his wife, Jackie.

Shevey, a former feature columnist in Hollywood, says she was asked by Monroe's friends to set the record straight. She is convinced that Robert Kennedy was "very responsible" for Monroe' s death. Robert Kennedy always denied being in Los Angles, but in the 1980s a police deposition came to light, where he admitted being in Monroe's house with Greenson.

"It is documented that he said he was holding her when she struggled, then holding her down while the doctor injected her," says Shevey. Was this a sedative or something more sinister?

So ended the life of the most famous woman in the world. As Monroe's body was wheeled out of the house it passed over a tile embedded in the entrance of the hacienda, with the Latin inscription, Cursum perficio, which translates as "I have run the course" - or "My journey ends here". It seems unlikely the journey will ever end.

Whodunnit: The conspiracy theories that enthralled fans

SUICIDE

Depressed about her stalled career and fading looks, plus the end of her affair with President John F Kennedy (and possibly with his brother Robert F Kennedy), Monroe takes an overdose.

Accidental suicide: Prescribed too many drugs by her Svengali-like psychiatrist, Ralph Greenson, she overdoses.

MANSLAUGHTER

Her housekeeper Eunice Murray and her psychiatrist, Greenson, administer a barbiturate-laced enema to calm Monroe down, which reacts with other drugs in her body with fatal consequences. When the police arrived, they find Eunice doing the laundry. Some biographers insist it was murder, with Greenson variously seen as a spy for the Comintern, the FBI or at least on the Fox pay roll. Murray, they claim, was in league with Greenson and had been sacked by Monroe the day before for insolence.

MURDER...

... by Robert Kennedy, JFK's younger brother, panics when she threatens to reveal her affair with JFK, and has her killed by lethal injection. Another theory is that he became her lover, and killed her to protect his career. He insisted he was in San Francisco on the night she died, but there were witness sightings of him in Los Angeles - even entering Monroe's house.

... by Joseph Kennedy, who was afraid that Marilyn would wreck his son JFK's campaign to be re-elected.

... by a member of the Rat Pack, to protect the Kennedys.

... by the Mafia, to blackmail the Kennedys after JFK declares war on organised crime.

... by rightwing nationalists, disturbed by the Kennedys' liberal agenda, or even as punishment for Monroe's marriage to Arthur Miller, a Communist sympathiser

... by the FBI: last year documents revealed that Monroe was one of a number of stars the FBI kept files on after applying for Russian visa.

... by Fidel Castro, in retaliation for attempts to assassinate him.

... by the CIA, to get even with the Bay of Pigs disaster.