By Laura Topham and Helen Weathers
For six years, her identity remained a closely guarded secret: a tantalising mystery for all those hooked on the stockings-and-stilettos tales of high-class call girl Belle de Jour.
A male fantasy with her Chanel nail varnish, lacy knickers, sexual tricks and vast knowledge of French cinema, the anonymous author of the best-selling memoir The Intimate Adventures Of A London Call Girl prompted a frenzy of speculation.
Was Belle real? Was she, in fact, a man with an exceptionally feverish imagination? After all, her sensational diary, which started life in 2003 as an award-winning blog and inspired a glossy TV drama starring Billie Piper, was considered by some to be almost too good to be true.
Well, now the truth is out and it is almost stranger than fiction. For not only is Belle de Jour real, but it emerges she is a high-flying, 33-year-old academic by the name of Dr Brooke Magnanti (pictured below).
A petite, American-born blonde, she has a PhD from Sheffield University in informatics, epidemiology and forensic science, and works at the Bristol Initiative for Research for Child Health, researching the effects of exposure to pesticides on foetuses and infants.
But she's now revealed that, as an impoverished student, she worked from 2003 to late 2004 as a £300-an-hour prostitute through an escort agency, pocketing a third of the fee for her two hour sessions with clients, whom she met two or three times a week.
Dr Magnanti "outed" herself on Sunday in a three-page interview in a broadsheet newspaper.
"Some sex workers have terrible experiences. I didn't," she said, swatting away criticism that her diaries glamorise a seedy, dangerous industry.
"I was unbelievably fortunate in every respect. The people at the agency looked after us appropriately and instructed us appropriately and weren't going to put us in harm's way if they could possibly avoid it."
How many men did she sleep with for money? "A lot. I can't honestly remember. Somewhere between dozens and hundreds," she says.
"I couldn't find a job in my chosen field because I didn't then have my PhD and I got through my savings a lot faster than I thought I would.
"Yeah, you could work behind a bar, but how many hours would you have to do to pay the rent? I couldn't get an overdraft, though once I started depositing so much cash, they offered me a mortgage within three months."
Why has she outed herself now? "I don't want this massive secret over me any more. It's changing the way I behave around people, the way I conduct my life," she says.
Mention was also made of a former boyfriend "with a big mouth, lurking in the background".
Could this be the man she referred to as The Boy in her diaries, her former boyfriend of seven years, who comes across as, in his own words, "a lumbering idiot"?
The man for whom she did not wear "work knickers" but, according to Belle's blog, "boyfriend knickers" ("Small. Thongs. Take-it-off-with-your-teeth type stuff")
A man described as so keen on bear hugs he could squeeze a rabbit to death. A man whose bedroom activities were pored over by millions of readers.
Step forward The Boy, whom we can reveal is a 35-year-old officer in the Armed Forces called Owen, who will soon be serving in Afghanistan.
He met Brooke in Sheffield in 2002 - the year before she started her blog - when she was studying for her PhD and he was working as an engineer.
He was aware of Belle's true identity from the beginning, and the escort work, but admits he was so blinded by love that he buried his head in the sand, refusing to read the blog in detail until they broke up a year ago
Until then, he'd assumed she was paid only for her scintillating company. He suspected her of sleeping with some clients, but thought this was because she was attracted to them, rather than because money changed hands.
Indeed, he claims Brooke told him - as the media storm about Belle's identity raged - that she'd sensationalised what had really happened with her clients in order to capitalise on the situation.
Given Belle's assertion on her blog on Sunday - "The non-Belle part of my life isn't the only 'real' bit. It's all real" - Owen now believes she was being economical with the truth.
He says he has spent years trying to protect her secret and is stung by the suggestion that he's the one with the "big mouth" when, he claims, he had to smooth things over and beg for silence when Brooke let the truth slip out accidentally to friends.
Indeed, the Mail can reveal that a more recent boyfriend bragged to his mates that he was sleeping with the real Belle de Jour and it was one of those friends who passed on her name to the newspapers.
Hopefully, this is not the boyfriend Dr Magnanti referred to as 'T' in her interview on Sunday, when she said: "He knew I was Belle before we started dating properly. He told me something that showed he trusted me, and I felt I could trust him back by telling him."
When the Mail tracked down Owen, he refused to talk about his former girlfriend. He has relented only because she has outed herself and, in doing so, outed him to his family.
We have agreed not to identify Owen by his full name, because to do so would result in immediate dismissal from the Army. But make no mistake, his family and many of his military colleagues and friends - who remember Brooke attending regimental dinners - know who he is.
"I was shaking when I read her confession. I can't believe she has done this," says Owen.
"She has brought the Sword of Damocles down on herself. While she thinks she hasn't been cut, I think she'll find that she has when she goes for another job in a couple of years.
"At least she has her literary career to fall back on, but what about me? Brooke has outed me to my friends and family without giving me any warning. People who have never read her blogs can look them up and see that The Boy is me.
"She has made a great deal of money from Belle de Jour, but I haven't received a penny and my life has been completely affected.
"She never asked if she could write about our life together and I feel humiliated. She hates me because she thinks I leaked her name, but I still love her and think about her every five minutes. I was planning to propose and had two rings made. I buried them on a beach where we used to walk together and watch the stars."
Reluctantly, given Brooke's startling admission, Owen now accepts the woman he adored was sleeping with clients at the same time she was seemingly in love with him.
"When she took the escort job, I begged her not to sleep with any of the clients. I remember standing in a London street saying: 'Please, please please, just keep that for me because sex belongs in a loving relationship'.
"She smiled at me, gave me a hug and a kiss and said: 'How sweet, of course.' I believed her. After that, I didn't ask about the work because I didn't want to know.
"You can say love is blind, that love makes a fool of you, but I thought it was 'knickers on' work, to put it crudely.
"I chose to believe she was a modern geisha rather than a high-class call girl, paid to chat to clients over a drink or accompany them to black-tie events."
But what on earth drove such an accomplished and educated woman not only to undertake sex work, but glamorise it through her blog?
A highly successful, widely read and intellectual woman with several degrees, Dr Magnanti was born in Florida, the Jewish granddaughter of Italian immigrants.
She attended Clearwater Central Catholic high school and went on to university in the US She moved to Britain as a postgraduate student at Sheffield, where she embarked on a PhD in computer visualisation, annotation and databasing of human skeletal remains.
Brooke first developed an appetite for blogs in Florida, where she started a website reviewing vegetarian restaurants. Under another pseudonym, she began a blog in 2002 about autopsies and a third under yet another nom de plume where she posted short stories.
Owen, who met Brooke on a night out in Sheffield, was used to seeing her tapping away on her computer and enjoyed reading her short stories.
"Brooke was cute and tiny," says Owen, who comes from a military family and went to public school. "As soon as I saw her, I knew she was different to every other woman I'd met - she was Fifties formal and ladylike, but with a great sense of humour. I fell in love with her almost straight away
"She was a lot more old-fashioned than people think she is and to me that was a good thing. We'd cook dinner, cuddle up and watch Monarch Of The Glen on TV while eating Scotch pancakes.
"I took her to meet my parents and they loved her. We were very happy together. The only dissimilarity between us was sexually - she was much more experienced and knowledgeable than me.
"It became apparent I was a country mouse in comparison. She is very adventurous and it made me feel really rural and old-fashioned. But I was a willing pupil.'
Owen says Brooke started working as an escort when she moved to London in 2003 because she had huge student debts.
She admitted in Sunday's interview that she has "a pathological aversion to being in debt" and had no moral objection to the concept of "hookerdom".
Indeed, she reveals that she has a relative who used to be a streetwalker to support a drug habit.
"She was sentenced for soliciting. She had several young children. I was told about it as a teenager - 'Ooh, she did such a bad thing' - but I never thought what she'd done was particularly bad," Brooke says.
Owen, close to tears, says he feels he is to blame for Brooke turning to escort work. In 2003, he'd been made redundant from his engineering job and could not support her.
He didn't like it when Brooke said she was joining an escort agency, but felt he was in no position to stop her. He begged her not to go any further than flirting. When Brooke was not working, she would often type away at her computer.
Owen says he became aware of the Belle blog early on, noticing similarities between himself and The Boy. He claims Brooke assured him the high-class hooker aspects relied heavily on artistic licence.
"Though she never asked me not to read the blog, I just decided not to," he says. "Maybe it was because I didn't want to see. The couple of times I did read them - when we broke up and I wanted to find out what was going on - I was deeply upset. It was awful."
The success of Belle de Jour - the name is taken from the Sixties film starring Catherine Deneuve as a bored housewife who turns to prostitution - would prove to be double-edged.
Owen remembers how thrilled Brooke was when she won a major blog award in 2003, and how reviewers compared her writing to that of Nick Hornby and Martin Amis.
Still believing the most explicit sexual parts to be fiction, Owen bought champagne to celebrate.
With book deals on offer and money suddenly pouring in, Brooke was reluctant to kill off Belle - even after she'd given up the escort work herself - because her creation had become the goose laying the golden eggs.
"Before Belle, her short stories used to be beautiful pieces about time and space," says Owen. "I always hoped she'd go back to that or write something about wildlife or science. But everyone loved Belle de Jour and her other writing had never received the same attention.
"I was prepared to put up with it because Belle wasn't the Brooke I knew. My Brooke was beautiful, funny, intellectual. My Brooke would walk along the beach with me, sit against hay bales and watch the stars.
"We would cuddle up or make jam together. I know that makes me sound like a soppy fool, but I adored her. I still do.
"Brooke is a clever, caring, thoughtful person, not the cold bitch she portrayed herself as Belle. She is much nicer than that and more fragile."
Though thrilled with Belle's soaring popularity, according to Owen, Brooke became increasingly paranoid about her identity becoming known, scouring the newspapers just in case her identity had been exposed.
Owen says she pored over the internet for images of herself, which she then had removed, and made him close down his Facebook site, which featured pictures of her.
"I didn't feel I could ask her to stop writing the blog, because she needed the money so badly. After it became a success, it became a trap," he says.
"I worked heaven and earth trying to give her all the money I could so she wouldn't have to work like that, but it was never enough."
Inevitably, their relationship struggled and they broke up frequently, which forms much of the storyline. Yet the success of Belle de Jour was unstoppable and Brooke swiftly landed an agent, then a publishing deal.
When the book came out in 2005, the deal was secured through various accounts and names to ensure absolute secrecy. Even the publisher did not know her real name. Her agent recommended she lay low to avoid being found out.
"Initially, I thought that it wouldn't carry on this long and that it would be easy to disappear again, that I wouldn't have to come out at all," says Brooke. "I thought I'd just fade away back to normal life."
In May 2006, Brooke landed a job that matched her real ambitions and abilities. It meant moving to Newcastle, where she researched gender effects in childhood cancer, funded by a grant from the Bupa Foundation.
Later that year, she bought a house and Owen moved in, though the relationship remained fraught.
"There were lots of ups and downs in our relationship, which was fiery and passionate," says Owen. "Brooke can be sweet and lovely, but she also has a temper."
Eventually, their relationship fell apart, with Owen claiming he caught her cheating on him four times. Since last summer, Brooke's boyfriend has been the man she refers to as 'T'.
At the beginning of this year, she moved to Bristol, where he was based, and took up her new role at St Michael's Hospital.
Meanwhile, Owen rattles around the house by the coast he bought for Brooke in the hope this would be where they would start married life together. All he has for company is the cat they both used to dote on.
On Sunday, Brooke was preparing to break the news of her double life to her mother in the US. She does not have any contact with her father, whom she describes as a "bit of a do-gooder ... he helps women".
Her Bristol work colleagues have known about Belle for a month and Brooke says they have been "amazingly kind and supportive".
Does she now regret writing the Belle de Jour blogs? "Sometimes. But, again, because of the writing, not because of the sex. And being anonymous is no fun - no jolly lunches to celebrate the book's success," she says.
"The blog will continue for the time being, even though it doesn't feel authentic to keep on being Belle. But I'll keep on for a bit. I'd like her to have a happy ending."
On Sunday, Owen - The Boy to Belle's fans - was receiving a few phone calls of his own.
From his shocked parents, brothers and friends, who'd all met and fallen in love with Dr Brooke Magnanti, too, and at one time expected her to become Owen's wife.
"I would forgive Brooke everything," says Owen. "I'd give anything to have her back."
So, no happy ending for The Boy, but does Belle de Jour even care? - Daily Mail