Princess Diana, her heart surgeon Hasnat and the astonishing family summit that sealed their love...
Dressed in a virginal white shalwar kameez bought specially for the occasion, Princess Diana stepped on to the long porch, out of the steamy 100 degree evening heat and into the cool darkness of the house.
She was looking forward to the next few hours with some trepidation. Even her years of battling with the devious plotters of Buckingham Palace had not quite prepared her for this.
There to greet her were eight senior members of handsome heart surgeon Hasnat Khan's family.
Diplomatically absent was Hasnat himself - the man Diana loves, the man with whom she wants to spend the rest of her life, the man who had made this visit necessary when he told her: "Yes, I will marry you - if you can persuade my mother to accept you."
Which was why Diana, in Pakistan to visit Imran Khan's hospital, tricked her security guards and slipped off to this extraordinary family summit at the Model Town home of Hasnat's uncle Jawad.
The Princess increasingly admires the Eastern way of life, and she felt instantly at home as she stepped past the piles of shoes in the doorway to meet Hasnat's family - his mother Naheed and father Rasheed, his sister Rabeeka and her husband, his sister Sanya, his aunt Maryam and her husband, and the family matriarch, granny Appa.
They began in the large, whitewashed sitting room, with its red and white patterned curtains. The floors are of cool stone covered with rugs. Around the room are wooden shelves and some of Hasnat's pencil sketches.
They all sat on expensive carved wooden easy chairs and sofas, where Earl Grey tea is served to special guests from an English antique-style silver tea service. The cups are fine porcelain, but they don't all match. They chatted about Hasnat and old family stories were recounted. Diana told them how she likes their way of life. She finds it relaxing and free from the pressures she has to cope with in her own life.
They all laughed when the power failed, and they moved out into the huge walled garden and sat under the mango and eucalyptus trees on the lawn.
Diana charmed the whole family, but she reserved her special attention for Hasnat's mother Naheed - the woman who believed the Princess wasn't good enough for her son and wanted him to marry a girl from his own aristocratic Pathan clan.
A family friend says: "She thinks Diana is not dignified enough. She has not proved to be loyal to her husband. That is the first requirement of a Pathan bride."
Naheed expressed her disapproval when Diana visited a mosque wearing a short skirt. "Perhaps she just didn't know our customs," she said at the time.
"She is beautiful no doubt, but this family stands for dignity. It is up to
us to marry Hasnat off. He should marry in our clan. "
Diana knew that Naheed was the final hurdle. She already has the tacit approval of most of Hasnat's family since granny Appa first visited Kensington Palace more than a year ago.
Appa, who is Hasnat's maternal grandmother, has since met the Princess several times. She refers to Diana as "my daughter" and treasures the official Christmas card Diana sent of herself with her sons.
"Appa likes the sweet nature of the Princess of Wales, chatting to AIDS patients and all," says Aunt Uzma, wife of Jawad.
"Natty must have told the Princess about how Appa follows her in the newspapers. It was a kind gesture for her to send the card."
His father Rasheed has said: "If my son and the Princess asked me for my permission to marry I would consider it."
Hasnat's cousin, American-based surgeon Naeem Khan Tareen, says: "Diana wants to marry Hasnat. They are in love." But while various relatives have tried talking to Hasnat about the relationship, he refuses to go into details. Uncle Jawad says: "He is avoiding us. Obviously he is embarrassed but he maintains it very well.
"He is an excellent, amenable fellow, witty and at times flamboyant. He plays cricket and squash when he gets the chance.
"But like a true Pathan he won't talk about his personal life. Outside the family he does what he likes.
"Natty won't even smoke in front of me or his parents."
His sister Sanya, 30, says: "It is high time my brother Natty got married.
"His bride must be pleasant, of course, and her first loyalty must lie with Natty and her in-laws. She must be mentally prepared to become part of this family."
Hasnat's favourite aunt Maryam adds:"Natty is much better looking than Omar Sharif. He is more like a young Marlon Brando, only tender, not full of himself. He is not macho like so many Asian men." So that left Naheed, the target of Diana's charm offensive.
And the Sunday Mirror can reveal today that it worked. Princess Diana and Hasnat Khan are, to all intents and purposes, engaged to be married.
As soon as Diana came home after last month's family summit, they sealed their love pact.
There is no ring, but the nature of their betrothal requires no such visible sign. A family friend in Pakistan says: "A ring is just a symbol. It is more a sign of friendship. It does not have the same significance to us."
The engagement is the latest stage in a romance first revealed to the world by the Sunday Mirror in January 1996. We told how, glowing with happiness, Diana had enjoyed candlelit meals with the handsome Pakistani heart surgeon she met at the Brompton Hospital in West London.
We revealed that Hasnat, senior registrar to the transplant pioneer Sir Magdi Yacoub, had visited the Princess at her Kensington Palace home. Then, in November last year, we reported how Diana, 35, wanted 38-year-old Hasnat to marry her and she was hoping to have a sister for William and Harry.
The flurry of denials convinced no one. Even last night, Diana's office would say only: "This is a private matter."
In fact, their love has continued to blossom. And in a bizarre coincidence, it is being encouraged by a couple who once found themselves with the same family problems.
Diana and Hasnat have been spending intimate, relaxed weekends at the Stratford Upon Avon home of Hasnat's uncle Omar, whose wife Jane is an English lawyer.
She went out to Lahore and faced the same rigorous grilling from the Khans, and the couple were married on the very lawn that Diana looked out on during the family summit.
Diana gets on with Jane because she has fitted in successfully to the Asian family. They often meet up in London and Stratford for lunch and social chats.
Meanwhile Hasnat and Diana go to quite extraordinary lengths to meet when they can get together for dinner and drinks in out of the way places.
She regularly slips out of Kensington Palace and races 100 miles to visit Natty in Stratford Upon Avon, or they meet at quiet country pubs near Harefield Hospital, where he works.
Two close friends are involved in the elaborate decoy plans and deceptions the couple need to meet without being spotted.
They have put a fleet of nondescript cars at Diana's disposal so she can slip out of town unnoticed.
But some of them are real old bangers. Friends have often marvelled how they actually make it to Stratford!
They also provide safe houses in West London for the couple to meet in private.
Last week Diana made another secret visit to Stratford, popping into Tesco to do a bit of shopping while staying with Hasnat's relations at their pretty town centre cottage.
Dressed in a pale blue cardigan and jeans she walked up the aisles with a male companion buying toiletries, a loaf of French bread and a bottle of wine.
She paid about pounds 20 at a check-out then returned about half an hour later with some children.
Startled shoppers stared as they filled two huge bags with pick'n'mix. Diana then hurried out and drove back to the Khans, who refuse to discuss her visit.
While Diana was in Tesco she parked in a disabled space, risking a pounds 25 fine.
The charity-conscious Princess nipped into the space ignoring dozens of legal empty ones.
Store security guard Trevor Leavesley said: "Normally I would have given whoever it was a ticket, but this time I didn't."
As she was leaving the store Diana stopped to chat at a helper at a hospice stall.
At home with uncle Omar and wife Jane, Diana can relax. She wears jeans, cooks with the family and washes up, spends evenings watching television and comes close to her dream of living a normal life.
Hasnat has also forged friendships with Princes William and Harry, whose approval was vital. Now, like any other couple, Hasnat takes the Princess out for meals and he picks up the bill.
They steer clear of London's high-profile celebrity restaurants, preferring more modest Stratford establishments such as The Italian Job and Greek Connection, where dinner for two with wine can cost as little as pounds 30.
And despite Diana's well-documented history of eating disorders, she tucks into whatever Hasnat puts in front of her. She is particularly partial to curry with pilau rice, and has even developed a taste for the Pakistani delicacy kulfi, a high-calorie frozen nut dish.
Hasnat is credited by some as being responsible for some of Diana's new confidence, and he is one of the few men who can cope with her moods.
Other members of Hasnat's family who live in Britain have visited Diana at Kensington Palace several times. She often lays on a traditional English afternoon tea for her special guests.
They also keep in regular contact with telephone calls and letters, and Diana has given granny Appa and other members of the family beautiful silver ornaments.
Previously Diana has flown all the way to Australia in the hope of a holiday with Hasnat away from prying eyes.
The plan was that she would use as cover a visit to the Victor Chang medical research unit. Royal insiders were baffled as to why the Princess would visit an unheard-of centre Down Under. Then it became clear.
Hasnat's early mentor was the late Victor Chang, Australia's most famous heart surgeon. He had planned to slip out of England and be with Diana during the official visit when she had a few days off at the end. But the secret tryst fell through when the plan was revealed before she even landed.
Hasnat has been confronted by some close relatives about the romance and refused to deny rumours.
At first he was happy to chat with friends and family about his "close friendship" with the Princess. But then he refused to discuss the relationship.
"He has never denied to me there is a relationship going on," said one of the close- knit family.
An excited Hasnat confided to one that he was booking a flight to Lahore early last February to be there when Diana was.
At the same time his family were gathering for a reunion to mark the end of the month-long Ramadan religious festival.
Some members of the family are sceptical about Diana's chances as the next Mrs Khan. But the Princess seems undeterred.
Having come up against the might of the monarchy - and survived - she feels equipped to cope with the Khans.
However, Hasnat often gives the impression that he is dragging his heels over making a more formal commitment to Diana after being jilted by two previous girls.
He was engaged to Nazra Nasim, a Pakistani doctor, who was his first great love. But she later married someone else and moved to France.
His second fiancee was Furial Anwar, who called off the engagement after 18 months. She still lives in Pakistan.
Another problem could be the question of children. Diana has said she love to have a little sister for William and Harry, while Hasnat has made it clear that babies do not feature in his immediate plans - he believes he should dedicate himself to his career.
However, one relation says: "Hasnat is no playboy. He is very balanced and very sensible, very homely."
Diana has picked up tips on Eastern ways from her friend Jemima Khan, who had to curb her Western playgirl lifestyle when she wed the Pakistani cricket hero Imran.
According to a royal insider Diana was envious of the attention Jemima's wedding attracted.
The blonde daughter of billionaire Sir James Goldsmith knocked the Princess off the front pages with her wedding to Imran - and has been heaped with praise in Pakistan for her dutiful role at her husband's side.
Now Diana is totally smitten with Hasnat and entranced by his intelligence, his caring manner and the life-saving work he does.
It's already clear that she is ready to adapt, even making changes to her appearance.
She has adopted the Eastern dark-eyed look and had her eyelashes tinted instead of caking on layers of mascara.
Unlike the friends Diana is used to, the Khans do not spend much money on glitz and glamour. Their cash goes towards the family's education. They are cultured, widely travelled and not at all star-struck by the rich and famous.
Diana says she wants a man with brains who can also understand her unique position in life.
One of her closest friends says: "She has learned she cannot always trust her own judgement. Diana needs someone she CAN trust, someone who will genuinely have her best interests at heart."
Diana now believes that, in Hasnat Khan, she has found that person. And with the approval of his family now gained, they can marry.
When she said goodbye to the Khan family after their meeting, they presented her with a beautiful hand-made shalwar kameez, the traditional dress of Muslim women.
But the Princess, happy and in love, came away from the family summit with much, much more than that.