WHEN Naim Attallah produced his book Women, I was one of the 300 who agreed — out of vanity? Curiosity? — to be interviewed over lunch in his private dining room at Quartet headquarters.

Attallah looked like the BFG — amiable, large-eared: he read out questions in a thick Palestinian accent from a clipboard on his lap. Transfixed by his intense, dark-eyed gaze, we all told him about our sex lives, marriages, childhoods, parents, ambitions and desires.

The resulting book, 1,200 pages produced at speed, was impressive. “There’s a woman up in Scotland,” I was told, “who does the actual writing.” Of course: he was a busy man, his English was imperfect, he would need an assistant to transcribe the interviews and shape the book. I thought no more about it.

But only now, with the publication of Jennie Erdal’s enthralling book Ghosting, does the extent of their collaboration emerge. Erdal wrote everything that appeared under Attallah’s name: the in-depth interviews, two novels, a newspaper column, letters, book reviews (she read the books; he didn’t).

A man of wealth and infinite largesse, Attallah had launched himself on the London publishing world in the Eighties, taking over Quartet Books, surrounding himself with “Naim’s harem” of well-born girls, and saving the Literary Review from collapse. Before he had any money, he told me, he had gazed at a diamond-studded Rolex watch in the window of Asprey, and promised his wife he would one day buy it. Now, he owned Asprey and — he drew back his cuff — here was the watch! In her book, Erdal does not name him but calls him “Tiger”. At first, he had loved the idea of being thus immortalised. “I am a tiger! I am a tiger!” he said delightedly. She sent him the first chapters and told him firmly: “I’m not going to make you out to be a saint. Saints are boring, by the way.”

“Yes, bloody boring! Saints are bloody boring!” But the book’s title is Ghosting: a word never mentioned in their 20 years together. And Attallah regards her book as a betrayal, though there was never any confidentiality clause or any sort of contract. Initially, he had even offered to publish it. But since it became clear that she was writing an honest appraisal of their collaboration and its weird psychology, he has not spoken to her. He is reportedly distressed (naturally) by her “exaggerations”.

Though he may not perceive it, she has in fact produced an affectionate portrait. She recreates vividly his exclamatory, physical way of talking,waving his arms, slapping his thighs, smiting his brow. “He was unconsciously hilarious, like a Dickensian character,” she says. “Magnificent in his self-importance, comical to write about.”

Erdal is a gifted writer. How, one asks, did she get swept up into deploying her literary craft on behalf of someone else? She had been the kind of child who wanted passionately not to displease her parents; and the same applied to her boss. Also, she desperately needed the money after her first husband suddenly walked out (“your self-confidence takes such a battering”), leaving her with three young children. She had to work from home in St Andrews. And Attallah was her financial salvation, for which she is forever thankful.

“At a very deep level he seemed to regard us as a single entity: he spoke about ‘we’ and ‘us’. But just before publication he would acquire sole authorship by some mysterious osmotic process. It was intriguing to observe. He really believed he was doing it himself. ‘They say we can write!’ he crowed as reviews arrived.”

Self-deception is a fascinating subject. His staff always knew the truth — and he did give her half his fees: the Express paid £500 per column, of which Erdal got £250. For the Women book, he paid her a bonus of £8,000. She fully acknowledges his generosity: her own generosity, letting him bask in the satisfaction of sole authorship, was arguably greater.

For the interviews she would intensively research each subject — Claus von Bulow, Diana Mosley, Lord Shawcross, Laurens van der Post — and prepare 50 questions, with colour-coded stage directions. She admits she could never have had the chutzpah to ask the tricky questions. And the end products were much lauded for “subtlety of interrogation” (William Trevor). Attallah was “a magician interviewer” (Robert Kee).

But when she drafted a question for an interviewee that included the phrase “skeletons in your cupboard” he was aghast. He’d never heard the expression. (“Naim Attallah is a dab hand with skeleton keys,” said Lord Deedes.) To show just how comprehensive their collaborative relationship was, she says she wrote a sensitive letter to his only son on his behalf, “and he was visibly moved”. He saw nothing morally questionable in getting her to write a 2,000-word review front for the Sunday Telegraph on abortion, from his Catholic viewpoint. That demanded a real leap of her imagination. “They had misspelt his name: he was so furious he cast the paper aside in disgust,” she says.

A travel piece about his visit to China was tougher. She had never been to China. Where had he stayed? At the Hilton Hotel. She began her research by reading a book of Chinese proverbs. “I opened it and saw, ‘Do not lace boots in melon field’.”