The lonely minister, the blonde and the honey trap

He has been the victim of a tabloid newspaper sting, and his love life is about to be lampooned on television. Francis Elliott, Whitehall Editor, investigates the hounding of David Blunkett

Returned to the Cabinet in short order, victorious in his paternity case against his former lover, he seemed to have recovered from a political near-death.

But a telephone call made that night from the club's Aladdin-themed interior has set in train a series of events that could put him straight back on the critical list. This weekend promises the denouement of a particularly duplicitous tabloid "kiss and tell", as the date he met that night goes public with details of what she claims was an "intimate" relationship.

While there is widespread sympathy for the manner in which a single, lonely 58-year-old man has been deceived, the affair has grave consequences for his credibility.

And should Sally Anderson, 29, the Ascot estate agent with a novel to sell and the publicist Max Clifford at her side, disclose Mr Blunkett's opinions of his colleagues, they may just be fatal.

Unpicking the details of this tale of love, cash and betrayal requires first an understanding of how it was that Mr Blunkett found himself sitting next to the well-spoken blonde in a Mayfair nightclub on 9 June this year. He had been asked to Annabel's by Tariq and Lucy Siddiqi. Mr Blunkett had briefly served with Mrs Siddiqi on the board of DNA Bioscience, a company that sells DNA testing, and it appears he had become friends with the socially ambitious couple.

Mr Siddiqi's track record as a businessman could safely be regarded as mixed, and there seems no shortage of former associates who have critical things to say about him. He certainly appears a formidable networker, at home in the highest circles. Having taken up polo, he soon managed to start organising events for the Guards Club. It was during this venture, which, typically, incurred heavy losses, that he met Sally Anderson then a 16-year-old schoolgirl.

Perhaps in Ms Anderson, Mr Siddiqi saw a kindred spirit. Originally from Hull, she had rid herself of any trace of a Northern accent and was determined to succeed, working first as a headhunter in the City and then as an estate agent selling homes to millionaires in Ascot.

An account of the first date between Ms Anderson and Mr Blunkett was given to The Sunday Times by a "friend" of Ms Anderson. Since it seems almost certain she planned to betray him from the first, it makes agonising reading.

He bought a box of House of Commons chocolates with him, and complimented her on the manner in which she guided him to the dinner table. They arranged to meet again but were photographed leaving. Just who tipped off the Daily Mail that Mr Blunkett was seeing a "mystery blonde" cannot be known for sure, but the call was made from a mobile phone in her name.

A well-spoken woman is reported to have said: "I think you should get your photographer down to Annabel's to see who is out on a date with David Blunkett."

Amazingly, the story was confined to media diaries. It seems clear that the Secretary of State for Work and Pensions thought his deepening friendship with the young woman would remain a private matter. How wrong he was.

Even as he took her to his Eaton Place home, where toys were spread around the floor - presumably evidence of his contact visit with his son, William Quinn - it appears she was secretly negotiating with newspapers.

A source called "Karen" was demanding payment for information about the couple and suggested cheques be made payable to an A King. The postal address given was a property on the lists of the estate agents where Ms Anderson worked. She is now with a 31-year-old businessman called Andy King.

Eventually, on the eve of Labour's annual conference, her identity was revealed, sparking a newspaper bidding war. Having engaged the services of Mr Clifford, Ms Anderson is thought to have sold her story for around £50,000.

A flavour of what she might have to say was given on Monday when she hinted she was privy to private conversations between Mr Blunkett and Tony Blair: "You would not believe the amount of times Tony calls him. He always seems to be asking: 'What should I do about this, what should I do about that?'"

Mr Blunkett has "form" for making indiscreet remarks about his cabinet colleagues, listing their faults in detail to his biographer. Figures such as Jack Straw, John Prescott and Charles Clarke remain suspicious of him as a result.

The telephone traffic between the Prime Minister and the Mr Blunkett is sure to be as fast and furious as ever this weekend. His spokesman continues to insist that his relationship with Ms Anderson was a "platonic" one and that she was alone with him on only four occasions. It seems likely that he will be able to count on the sympathy of many as he weathers the storm created by the latest disclosures, and as a dramatisation of his infamous affair with Kimberly Quinn goes out on digital television.

He has already authorised sources to say he will not be returning to Annabel's. "He knows it was unwise."

But worryingly for his long-term prospects, other colleagues are less understanding. "Of course it's bloody sad but the view among some of us is why does he keep dating these high-society types?" says one. "There are plenty of decent Sheffield lasses that would be happy to have him.

"And when he gets up later this month and starts trying to sell the Government's message on pensions or welfare reform, everybody is just going to be thinking of what he got up to at Annabel's."

There is a curious irony that Mr Blunkett - a supreme media manipulator in his own field - should have been such easy meat for the tabloids. If he has once again been critical about his colleagues he will need all his skills - and (real) friends - to survive.

'A Very Social Secretary' is on the digital channel More 4 at 9pm tomorrow