Mrs Blair and the blackmailing fantasist

The woman who was restrained by a judge this week from publishing malicious gossip about the Blairs' private life is called Nel Lister. Or is it Oonagh Mary Flynn? Or Nell Rubens? Is she a child protection officer, as she claimed in court, or a Russian ballerina, or a secret agent, or a helicopter pilot, or, indeed, the former lover of murdered SAS officer Captain Robert Nairac? She is all of these things, and none. All we can be sure of is that she is a liar of breathtaking audacity. But don't just take our word for it, ask her father, or her sister, or even her children ...

"He's a barrister, and she is, and they employed an expensive legal team. How come none of them thought to ask some basic questions about who was this woman they were dealing with?" asks Bill Flynn. The 87-year-old already knew the answer, however. Fifty years of anguish has carved it into his heart.

"He's a barrister, and she is, and they employed an expensive legal team. How come none of them thought to ask some basic questions about who was this woman they were dealing with?" asks Bill Flynn. The 87-year-old already knew the answer, however. Fifty years of anguish has carved it into his heart.

His question was addressed to Tony and Cherie Blair. And the woman he was speaking of is the author whom a judge at the High Court this week pronounced had effectively blackmailed the Prime Minister's wife - by demanding £40,000 in return for stopping work on a book which alleged that a story of child neglect lay behind the "rosy version" of the Blairs' family life which is presented to the public. The judge ordered the author to "fillet" her book of any information which had come from the Blairs' former nanny, Ros Mark. He also ordered her to hand over three computer disks and pay £15,000 costs.

The accusation had caused deep consternation to the Blairs. "They knew that none of it was true," said one of the family's inner circle. "But they knew that this woman could have said anything in court and the allegations, however wild, would have been reported. The fear is that mud sticks, however untrue. And we knew nothing of who this Nel Lister was."

Nel Lister, the woman behind the book, who has befriended the Blairs' former nanny, told the court she was a child-protection officer. "In fact she is nothing of the kind. She is my daughter," says Bill Flynn, a former court official from Merseyside, "and all her life she has been involved in a succession of scams, frauds, deceptions, lies, and forgeries. If only Downing Street had checked with Scotland Yard."

Yesterday the Anti-Terrorist Squad at the Yard contacted the Downing Street police protection unit and offered information from its file on Oonagh Mary Flynn, alias the aforementioned Nel Lister, aka Nell Rubens, Nell Rubens-Lister, etc, etc. At the heart of the Anti-Terrorist Squad's investigation was the false claim by Oonagh Flynn that she had been the secret lover of Captain Robert Nairac, the SAS officer who was murdered by the IRA while working undercover in Northern Ireland in the Seventies. In the event the claim - which included serious accusations about nefarious activities by the British Army in Ulster at the time - was proved to be a confection dreamt up to extract a large sum of money from a tabloid newspaper. And it was only one of many such scams.

Oonagh Flynn has always been a liar of breathtaking audacity. Over the years she has posed as the child of Jewish refugees, a British secret agent, a psychologist, a Russian ballerina, a helicopter test pilot, and a captain in the US military - all of which make purporting to be a child-protection officer sound positively modest.

It began with large-scale versions of childish fibs. "She claimed her brother had died to get herself sent home from a convent in Brussels once," Bill Flynn recalls. "I myself have died at least three times when it has been convenient for her to have to go to my funeral to get out of something." Once she posed as a sex-education expert to a group of nuns and gave outrageously graphic sex lessons to their pupils.

But her Walter Mitty world soon crossed the border into illegality. "It began with fur coats and jewellery going missing when she was an au pair in Rome, and soon landed her in court," her father recalls. "She convinced someone that she was a British secret-service agent who needed £700 in cash quickly to pay an informant, and then she did a runner with the money."

The first time, she got away with probation, though after being held on remand in Holloway Prison she was sent to Horton mental hospital for a time. There was a non-custodial sentence, too, the next time when - having got a job and a house at a caravan park in the Lake District after saying her husband had been killed by IRA - she sold one of the caravans (which belonged to the then Lord Mayor of Liverpool and a finance company with whom he had a loan). The third time, a catalogue of fraud and deception convictions in Lyme Regis earned her a 12-month sentence in Holloway. Since then she has been found to have applied for loans in other people's names without their knowledge, and she has left behind her a trail of unpaid bills and bad loans all over the country.

"The greatest irony is that she now turns up posing as a child-protection officer - she's got a cheek, after the way she treated us," her son Patrick, now in his late twenties, tells me. "It was a catalogue of mental and physical abuse." On a number of occasions her three children were the subject of social services' scrutiny, put on the "at-risk" register or taken into care.

"We were also brought up in constant fear of saying the wrong thing to the wrong person," Patrick continues. One day she was Anya Andreivna, talking in fake Russian tones, the next she was turning up at her son's boarding school in the full uniform of a US captain, talking with an American accent.

That was bad enough. What was worse was when Oonagh began to draw the children into her murky world. Patrick was forced to act as a money courier, which got him into trouble with the police. Her younger son, Robert, who was good with computers, was made to help her forge documents. "She is a past master at doctoring stuff and airbrushing," her father says. Her brother, Bill, a member of the Territorial Army, once discovered army files she had stolen and doctored; he returned them to military security. In another court case, in Reading, she was found by the judge to have stolen notepaper from the accountancy firm where she worked as a cleaner, and used it to forge "evidence".

It was when she began to cause mayhem among the staff of an Aids trust in Plymouth - where she had got a job with false references and qualifications - that her family decided to abandon their previous policy of trying quietly to make good the countless problems she had caused. Her sister, Nonie Covill - on behalf of Oonagh's other siblings, her father and her three children - wrote an open letter to all the parties to the dispute, which included the South West Devonshire Health Authority and the local social services.

It said: "Since adolescence Oonagh (Nel) has suffered from a personality defect which has manifested itself in unstable, volatile and aberrant behaviour. She has shown no understanding of truth or the rights of others. These factors, combined with her sharp intelligence and highly creative imagination, have proved a dangerous combination resulting in a series of crises throughout her life. Frequently other people have suffered as a result."

The pattern of behaviour which underlay all this, the family said, was that Oonagh had assumed a variety of identities, and fantasised about her qualifications and experience across a wide variety of careers. She had consistently incurred serious debts - often by criminal deception - in her attempts to maintain fantasy lifestyles. She made unfounded serious allegations against many people - family included - who began to question or express disapproval. She exhibited multiple profiles to different people and expended a lot of energy keeping these people apart for fear of them comparing stories. She had manifested a sort of transference, accusing others of things she has done. And she had applied to herself dramatic events or situations she has read about.

"She reads a book and out of it comes her next persona," says her sister, the actress Kate Flynn. "She has an amazing ability to suck up information, reformulate it and project it back to people." Which is exactly what she did when a new book about Robert Nairac, Death of A Hero, came out. "Suddenly she entered into the Nairac world, even though throughout the period covered in the book she had actually been in Warrington not Northern Ireland."

The Sunday Mirror fell for her story. "My doomed love for the undercover soldier who always knew he was going to die," said the headline under its World Exclusive tag. "You couldn't blame them," says her father. "She's always well-researched. She's very plausible, intelligent, and sure of herself." But the photo alongside the caption: "On a romantic weekend break Nairac took photos of Oonagh wearing only his Army camouflage net", was in fact taken by the fraudster's daughter, Nicola, in Lyme Regis, at Oonagh's own request. And the shot of Oonagh with a broken nose, "having been assaulted by British secret service agents", was in reality taken after a client had punched her at Brixton Advice Centre.

But deception is a two-sided process. The MP Ken Livingstone refused to believe information from Oonagh's family, and continued to insist that her story "confirms the scale of what was going on, sanctioned by MI5, in Northern Ireland. It was effectively state-backed murder." But Oonagh's whole story - along with her central claim that Nairac was the father of her son Robert - was discredited not longer afterwards when Robert decided to have a DNA test. The results proved that his father was not the SAS man, but a factory-worker from Warrington.

Then things went quiet - until, at the end of October, Oonagh sent a letter to her son Robert from China, saying that she would be teaching in a school in Xian province for 12 months before going on to Nepal for a further year. Just two weeks later the unhappy Flynn family opened their newspapers to discover that Oonagh was back, photographed outside the High Court after her battle with the Prime Minister's wife.

"We tried to respond to her Northern Ireland scam discretely and quietly, because we were aware of the distress it must cause to the Nairac family," says Patrick Lister. His family had privately contacted concerned MPs, including Ken Livingstone, and co-operated with officers from Scotland Yard's Anti-Terrorist Unit. "But we decided not to say anything in public because that would just feed her craziness."

They hoped, as they had hoped dozens of times before, that Oonagh might, given quiet anonymity, begin to change as she had so often promised to do.

"We were wrong," her son says. "Instead, she is back, more high-profile than ever, doing damage to people's lives as she always does. Accusing Cherie Blair of child neglect and all the rest of it is so completely outrageous. We decided that this time we couldn't stay silent."

The world, her family have decided, needs to know about Oonagh Mary Flynn - and beware.