"She won't go quietly, that's the problem," promised Diana Princess of Wales, royally referring to herself in the third person, during the now infamous interview with the BBC's Panorama programme in November 1995. Twenty-one months later she died following a car crash in Paris which is still the subject of acrimonious debate. For a woman often unfairly dismissed as a lightweight, Diana was remarkably prescient. During the interview she also said: "I'd like to be a queen of people's hearts but I don't see myself being queen."
Her companion Dodi Fayed also died in the crash. This unremarkable man - a multimillionaire "playboy" figure - had enjoyed the predictable trappings of wealth: polo-playing on Daddy's estate, a swish, serviced apartment in Mayfair, sojourns on the family yacht and an undemanding, glamorous "job" in film production. Men like that rarely impinge on the public consciousness but in 1997 Dodi entered the eye of the storm. By striking up a liaison with the world's most famous, photographed and talked-about woman he quickly became a household name.
An exhaustive inquiry by a French judge into the circumstances surrounding their deaths interviewed over 200 witnesses, took two years to complete and resulted in a 7,000-page report which concluded that Diana and Dodi died when the car in which they were travelling at speed from the Ritz hotel hit the central reservation in a tunnel. The chauffeur, Henri Paul, who also died, was blamed for being under the influence of alcohol and medication and for driving too fast.
And that should have been the end of the matter - allowing the couple to rest in peace and their families to get on with their lives. But these are no ordinary families. Relations between Mohamed Al Fayed, father of Dodi and owner of Harrods, the opulent west London department store, and the British royal family - who should have been united in grief - are utterly poisonous.
Mr Al Fayed refuses to believe that the crash was an accident. He remains convinced that there was a conspiracy involving British intelligence services to murder Diana because she was pregnant with his grandchild and the couple planned to marry - events which he feels would have been quite unacceptable to the establishment. He has accused the Duke of Edinburgh, Queen Elizabeth's husband and consort, of leading a cover-up.
There is no evidence to support the theory that Diana was pregnant but some to support the claim that Dodi planned to propose on the night that they died. He had allegedly bought a £130,000 diamond and emerald engagement ring from society jeweller Alberto Repossi in the Place Vendome. And Diana herself had mysteriously told journalists a few weeks earlier: "You are going to get a big surprise with the next thing I do."
Mr Al Fayed is unhappy with the French investigation into the crash, which he believes failed to answer many questions. Among many gripes, he contests the claim that chauffeur Henri Paul had been drinking and has tried unsuccessfully to get access to the blood samples to arrange independent testing. And he also continues to offer a reward of over €1.5 million for "new" information, especially relating to a mysterious Fiat Uno allegedly involved in the crash at the Alma Tunnel, Paris, on August 31st, 1997.
Mr Al Fayed was devastated by the untimely death of his son. Dodi is buried on the grounds of the family estate in Surrey, his Mayfair flat has been "preserved" exactly as it was when last used by himself and Diana and, most notoriously, there is a garish "shrine" to the couple - featuring the supposed engagement ring - in Harrods. The Knightsbridge store for decades enjoyed the patronage of members of the royal family, which meant the shop could display the coveted royal warrants. But in 2002 Al Fayed snubbed the royals by removing their crests from the façade of the famous building. All Harrods packaging and stationery was redesigned and the famous green vans which provide home deliveries to rich customers across London had their royal crescents painted over.
Mr Al Fayed, who has described the official Diana Memorial Fountain in London's Hyde Park as a "sewer", recently unveiled a second memorial in Harrods, a bronze sculpture depicting the pair, entitled "Innocent Victims". He said: "I am a father who lost both his son and a great friend in Diana, and like anyone else in that position, I will fight until my dying breath to get the truth. Many people have tried to silence me, but I will not be deterred in my quest for the truth. Even now, eight years on, I am uncovering evidence which will prove these beautiful young people were assassinated."
To judge by the mawkish comments in the visitors' books, the sculpture is much admired by fans of "the people's princess", but has been the subject of snooty comments by establishment figures. Dodi is depicted in an unbuttoned shirt - a surefire sign of a cad among the upper classes. Kate Fox, a social anthropologist writing on English dress codes, explains: "Shirts unbuttoned to display an expanse of chest are lower class - the more buttons undone, the lower the class of the wearer".
Clearly rattled by the ongoing controversy, and irritated by the persistence of conspiracy theorists, the British government has set up an inquiry led by the former Metropolitan Police Commissioner, John Stevens, to investigate the circumstances surrounding the crash. The inquiry, involving a full-time team of 14 police officers, has to date cost an estimated £3 million, visited Paris, shipped the mangled remains of the Mercedes car back to Britain for further forensic tests and is interviewing an array of witnesses including even Prince Charles.
It is expected to conclude some time early this year. Only then will the official, and separate, inquests into the deaths of Diana and Dodi - already opened and immediately adjourned - be reconvened.
There is no likelihood, any time soon, of Diana going quietly.