ONE of the literary world’s most carefully guarded secrets might now be out. New clues have emerged as to the identity of Belle de Jour, the diarist who set pulses racing with her supposedly true account of life as a call girl.

The evidence points to Belle being largely the work of Lisa Hilton, a British author based in America, who has written about her own steamy sex life in the past. She has been outed on the same weblog, or blog, forum where Belle’s diaries first began recounting the exploits of the stiletto-heeled sex bomb who ravished her man before discussing French poetry with him.

The new blog is remarkably convincing as it contains a number of details that would be known only to someone very close to the original author. It even correctly named the obscure front company run by Belle’s real-life agent.

Entitled Belle de Hypothesis — Fictional Account of a London Publishing Scam, it says the original blog was “conceived by a coterie of young women who saw it as an appropriate vehicle to vent their frustrations with various aspects of their personal and professional lives”. It refers to the women only by their initials, parodying the style of the original. One of the main instigators was “LH” who it says has “northern roots”. This appears to refer to the Cheshire-born Hilton.

LH, it says, wrote an article for a Sunday newspaper about “dirty weekends in Brighton” as well as a column for The Erotic Review — as did Hilton.

Also identified as being involved in creating Belle is “RP” — Rowan Pelling, former editor of The Erotic Review.

According to the hypothesis, the women used their access to national newspapers to publicise the blog until it drew the attention of “PW” — Patrick Walsh, who later became Belle’s literary agent. “He arrived by e-mail, introducing himself with an offer which astonished the coterie,” it claims.

Pelling initially wanted to reject his offer, though Hilton needed the cash, the account says. Hilton consulted her friend “TY” — Toby Young, an author and journalist previously suggested as the writer of the diaries — for advice on whether to accept.

The account also refers to Bizrealm, a company owned by Walsh and of which he is sole director, and to which copyright of the book was assigned to avoid revealing who wrote it.

Hilton’s own exploits and sexual mores make her a particularly interesting candidate. The Oxford English graduate, now living in New York after spells in Paris, Milan and London, has already written a detailed and candid article exposing her own sexual adventures. She is also author of a biography of Athénaïs, spurned mistress to Louis XIV.

She says she is a self-confessed “fan of adultery”, who believes that “perhaps the best thing about marriage is that it makes illicit sex a possibility”. The hypothesis says that LH has now married an Italian musician.

Hilton had divorced twice by the age of 26, going on to write frankly about her subsequent affair with a married man.

Before the launch of Belle’s diary, Hilton, 28, admitted: “I enjoy the indulgent consumerism of being a mistress tremendously. Proper relationships are for joint excursions to Sainsbury’s; adultery is for licking crème de marrons off your lover in a hotel suite when he’s meant to be at a conference in Basingstoke.”

Within 16 months of publishing her frank diary online, Belle had spawned speculation about her identity, secured a literary agent and television deal with Channel 4, and written a bestselling book.

Speculation about Belle’s identity has been rife. Apart from Young, other candidates have included the author Isabel Wolff and the Mancunian music journalist Sarah Champion, who is now based in America. Both have denied involvement.

Hilton, a former nanny, model and roller-skating waitress, said last week: “I am afraid I can neither confirm nor deny (involvement). I really do not want to say it is not me, because I do not want to engage to that extent.

“I really do not want anything to do with it. I have never read any of this woman’s writing. I know nothing about her. As far as I can see it is just tittle-tattle and coincidence.”

A spokesman for Hilton’s agent later insisted she had no involvement.

Pelling, 37, said she had met Hilton on only a couple of occasions. “It’s nonsense. There is no link. I have met Belle once, and I think she is who she said she is,” Pelling said.

A reply to an e-mail to Belle from The Sunday Times, asking whether she plans to identify herself, also sheds little light on the diaries’ author. She said, with typical good grace: “Darling — no, thank you.”

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