A new book reveals the extraordinary contents of Marilyn Monroe's private filing cabinets, thought lost for over 40 years after her death
© Mark AndersonDetail of a test print from the Marilyn Monroe archive.

In November 2005 Millington Conroy, a businessman living in Rowland Heights, 40 miles east of Los Angeles, contacted Mark Anderson, a successful magazine photographer, to discuss an unusual commission.

He had in his possession two metal filing-cabinets, one brown, one grey, containing private papers and a collection of furs, jewellery and other assorted memorabilia, all belonging to Marilyn Monroe. Would Anderson be interested in photographing the collection?

The material - about 10,000 documents - had been thought lost for more than 40 years since the death of Monroe on the night of 4 August 1962. Now, here it was, a treasure trove, languishing in a Californian suburb.

It was the commission of a lifetime, the largest undocumented Monroe archive in existence. Yes, of course Anderson was interested, and, with the help of the biographer and Monroe aficionado Lois Banner, he set about creating a record of the archive's contents, which is now to be published for the first time as a book.

There are letters from Monroe glowing with admiration for Robert Kennedy; a half-finished love letter to her ex-husband Joe DiMaggio found in her room after she died from a drug overdose; unseen pictures of Monroe as a child and young woman; touching fan mail; rare insights into her marriage to the playwright Arthur Miller; and extensive documentation of her squabbles with the Hollywood studio Twentieth Century-Fox.

In these documents the flesh-and-blood Monroe, usually lost in the heady blaze of the images of her on film and in glamour photographs, comes alive in the flotsam and jetsam of everyday life.

We can see her bookshop receipt for The Life and Works of Sigmund Freud, volumes one, two and three (she was a slave to therapy); the newspaper cuttings, both flattering and critical; her witty little telegrams. Then there are the bills for enemas, facials and prescription drugs, the uppers and downers that in her later years carried her through the day, and eventually killed her.

Frank Sinatra, one of Monroe's lovers, is said to have suggested she buy the filing cabinets to protect her privacy when she was living in New York in 1958. In early 1962, when she moved to Brentwood, Los Angeles, she had the cabinets shipped down.

The grey one, containing private correspondence, was kept in the guest cottage at the Brentwood house; the brown one, containing business records, was stored across town in her office at Twentieth Century-Fox studios.

One account of Monroe's last night claims that she actually died in the guest cottage and was subsequently moved to her bedroom in the main house and rearranged on her bed.

What is certain is that sometime on the night of 4 August the cabinet in the guest cottage was broken into, and that crucial files were removed - perhaps pertaining to Monroe's relationship with the Kennedys and their links with the Mafia boss Sam Giancana, perhaps to her contractual arrangements with Twentieth Century-Fox.

How did these immensely valuable cabinets manage to vanish for so long only to resurface in a quiet corner of suburban California? The key to the mystery is Inez Melson, Monroe's business manager in the mid-1950s, guardian of Monroe's schizophrenic mother, and, following Monroe's death, administrator of her Los Angeles holdings.

In the days and weeks after Monroe died Melson, who received nothing in Monroe's will (the bulk of the estate and her personal effects were left to Lee and Paula Strasberg, her acting coaches), made sure the filing cabinets ended up in her possession.

She had the brown cabinet at Twentieth Century-Fox transported to her home in Hollywood Hills, and, fraudulently, using the name of one of her nephews, bought the grey cabinet for $25 at the Monroe Estate auction she herself had organised. Upon her death in 1985 Melson left her collection, including the cabinets, to her sister-in-law Ruth Conroy, who, upon her death, bequeathed it to her son Millington.

In the course of their research, it soon became apparent to Anderson and Banner that Melson had acquired the contents of her archive illegally and that Strasberg's third wife, Anna, was in fact the legal owner of the material.

'We told Mill what we had found,' writes Banner. 'Realising that his ownership of the collection could be in jeopardy, he threatened to sell it on the black market... We wanted to ensure that the [collection] remained intact and that it would eventually be shown to the public; so we informed Anna Strasberg of its existence. We were not privy to her ensuing negotiations with Mill. All we know is that, in the end, they reached a settlement.'

What is astonishing about the archive, says Banner, is quite how much material has survived, and also its quality. Amid the mass of bills, cheques, contracts and publicity shots there are insights into the most private corners of her life.

Monroe grew up effectively an orphan. She never knew her father, and her mother's illness meant Monroe spent her childhood and teenage years being passed from family to family, including a spell at the Los Angeles Orphan Home. She was left with a lifelong desire to truly belong in a family, and to bring up children of her own.

Monroe's horror at the idea of not being able to get pregnant is made starkly and rather zanily clear by a handwritten letter she taped to her stomach before having her appendix removed in 1952: 'Cut as little as possible,' it reads. 'I know it seems vain but that doesn't really come into it. The fact I'm a woman is important. You have children and you must know what it means. For God's sakes Dear Doctor no ovaries removed.'

Monroe suffered three miscarriages in the mid-1950s while married to the playwright Arthur Miller, and the archive is full of reminders of how painful that time must have been. There's a receipt for a maternity dress Miller bought, and a letter of condolence from the poet Louis Untermeyer, which sums up the paradox of her life - at once adored by millions and isolated in her suffering: 'It's grimly ironic that while the rest of the country was enjoying the comedy of your impersonations in Life [the December 1958 issue had a shoot in which Monroe spoofed the great sirens of history], you were going through your personal tragedy... Arthur's tribute was a model of good taste, artistic balance, and love. It must be an added comfort to know that everyone loves you - especially now.'

Most extraordinary is a letter she and Miller received on 24 January 1958, in the aftermath of her third miscarriage, offering them a child to adopt: 'Wonder if you might be interested in the adoption of a baby girl, that was born to an unwed mother about the same time your wife lost her child. It is a healthy and beautiful baby and the mother feels that you people would really make a good happy home for her... If you are interested you can reach me by phone.'

Would Monroe have been a good mother? Who can tell? But letters she wrote to her stepchildren, Bobby and Jane Miller, reveal a playfulness and understanding of childhood needs and disappointments that would surely have stood her in good stead.

In August 1957 we find her writing to them at summer camp in the guise of their basset hound, Hugo (she also wrote to them as their Siamese cat, Sugar Finney): 'It sure is lonesome round here! I made a mistake and I am sorry, but I chewed up one of your baseballs. I didn't mean to. I thought it was a tennis ball and that it wouldn't make any difference but Daddy and Marilyn said that they would get you another one, so is it all right for me to keep playing with this one as long as you are getting a new one? Love from your friend and ankle-chewer.'

The light-hearted, but slightly wistful tone of these letters (the word lonesome crops up again and again in her letters to the children at this time) are made more poignant by the fact that on 1 August Monroe had suffered her second miscarriage.

Anderson and Banner's selection of material presents Monroe in a positive light. She is a woman fighting to control her image in a man's world; a talented comic actress compared by directors to Garbo and Chaplin; a caring stepmother; a clever correspondent; a trustworthy friend.

The authors do not, however, gloss over her petulance ('I am exceedingly sorry but I do not like it,' reads her curt telegram to Twentieth Century-Fox on being sent the script for Pink Tights, which she'd already decided she did not want to make); nor over her refusal to compromise, which during the filming of The Misfits led to Dorothy Jeakins - a major Hollywood costume designer who had done costumes for Monroe on both Niagara and Let's Make Love - leaving the film ('I'm sorry I have displeased you. I feel quite defeated - like a misfit, in fact,' wrote Jenkins). Angry legal spats also bear witness to her legendary lateness, which resulted in almost everything she worked on running over schedule.

Despite knowing how infuriating she could be, it remains impossible not to like Monroe. She had a wit worthy of Mae West ('There is only one way he could comment on my sexuality and I'm afraid he has never had the opportunity!' she wrote of Tony Curtis, though he would later claim to have been her lover) and an ability to remain winsome even in adversity.

After she was fired from the film Something's Got to Give in 1962, as her drug habit escalated, she wrote to George Cukor, the director: 'I blame myself but never you. The next weekend I will do any painting, cleaning, brushing you need around the house. I can also dust.'

Marilyn always said it was the people and not the studios who had made her famous, and we see the best of her when she reaches out to her public. She received thousands of fan letters each week, and was meticulous about filing away those that had particularly touched her.

There is a charming letter from a 17-year-old Italian boy, who is clearly entirely overcome: 'I imagine that you and I dance wrapped in a sky of stars, and they smile on us.' He requests a lock of Monroe's hair. Monroe is clearly touched because along with the letter is found a note by her: 'Pic of him and dedication autographed and returned also a lock of hair. Also a letter which I will carry next to my heart always.'

Equally moving is a note from the mother of a soldier who saw Monroe perform in Korea in 1955. She quotes from the letter her son sent her: 'When she appeared on the stage, there was just a sort of gasp from the audience - a single gasp multiplied by the 12,000 soldiers present... The broadcasting system was extremely poor... However, it didn't matter. Had she only walked out on stage and smiled it would have been enough.'

If representatives of the Kennedys did remove documents from the filing cabinet on the night of Monroe's death, and Lois Banner is certain that they did ('I know who took them and what happened to them, but I don't feel at liberty to say at this point,' Banner told me), they were pretty thorough. The archive now has almost no material relating to Monroe's relationships with JFK and Robert Kennedy, which are thought to have dominated the final months of her life.

Tantalisingly, she makes two references to Robert Kennedy in letters written on 2 February 1962, the day after she had attended a dinner in the attorney general's honour. To Arthur Miller's son, Bobby, she writes: 'I had to go to this dinner last night as [Robert Kennedy] was the guest of honor and when they asked him who he wanted to meet, he wanted to meet me. So, I went to the dinner and I sat next to him, and he isn't a bad dancer either. But I was mostly impressed with how serious he is about civil rights.'

She is rather more circumspect when relating the incident to Miller's father, Isidore: '[Robert Kennedy] seems rather mature and brilliant for his thirty-six years, but what I liked best about him, besides his Civil Rights program, is he's got such a wonderful sense of humor.'

Smitten? Maybe. There are certainly no other letters here that emanate this wide-eyed flirty glow. But the remaining documents from Monroe's last spring and summer offer no hint as to where this relationship might have gone.

Instead there are ledgers and memos charting the increasingly poor state of Monroe's finances and revealing that her main expenditure was on medical bills. There is an eerie absence of anything else. Where are the letters from friends, the fan mail, the urgent telegrams of former times?

Stolen, perhaps? Or had the isolation that Marilyn always so feared begun to close around her. The only hint of human warmth to be found among a sea of cheques and tumbling balances is a note, signed with a heart, from Monroe's acting coach Paula Strasberg: 'Have faith,' it reads.

MM - Personal: From the Private Archive of Marilyn Monroe (Abrams, £22.50), by Lois Banner with photographs by Mark Anderson, published on Tuesday [Feb 22nd], is available from Telegraph Books (0844 871 1515; books.telegraph.co.uk) at £20.50 plus £1.25 p&p