The official version, the conspiracy theories and the evidence surrounding Princess Diana's death.
Was Diana's driver drunk?
A few hours after the crash, French authorities carried out drink and drugs tests on Henri Paul, the driver of the car carrying Princess Diana and Dodi Al Fayed.
He was found to be three times over the French drink-drive limit. Concentrations of prescription medicines also found in his blood suggested that Paul had been taking Prozac, an anti-depressant, and Tiapridal, sometimes used to treat alcoholics.
The blood results were leaked to the press within 24 hours, sparking critics to believe that a cover-up was in the making.
The Ritz Hotel, where Henri Paul had been the deputy head of security, denied he had been drinking and released CCTV footage to show he was sober.
Conspiracy theorists claim Paul would have been unable to function normally under that much alcohol and point to CCTV released from the Ritz Hotel, which they say show Henri Paul walking and talking normally in the hotel, on the night of the crash.
They argue that Henri Paul's blood had been switched at the morgue, in a bid to hide the truth that Princess Diana was murdered.
French police did further blood tests to check his alcohol levels Judge Herve Stephan, the French investigator appointed to the crash, was present and photographed the post-mortem. The tests gave very similar readings.
But Henri Paul's blood also showed a high amount of carbon monoxide, 20.7%. This further fuelled the conspiracy that Paul's blood had been switched.
At the inquest, the court heard confirmation from the Ritz's bar staff that on the night he had definitely had been drinking. He ordered and drank two Ricards - roughly the equivalent of four single measures of whisky.
And if the blood tests are to be believed he had drunk more than the equivalent of another litre of wine.
The carbon monoxide levels have never been satisfactorily explained but French police denied a conspiracy to tamper with the blood.
The jury's verdict was that Henri Paul's driving had definitely been impaired by alcohol - and this contributed to the unlawful killing of Diana and Dodi.
Was Diana's driver speeding?
Princess Diana's Mercedes sped from the back of the Ritz hotel along a dual carriageway on the River Seine, to try to escape paparazzi on its way to Dodi's apartment on the Champs Elysees.
But just four minutes after its departure, the Mercedes crashed into the 13th pillar of the Alma Tunnel.
Forensic and crash experts were called in to assess the skid marks left in the tunnel and the damage to the Mercedes.
Returning the car to its original position in the Alma Tunnel, they used lasers to try and work out the trajectory of the Mercedes' path before hitting the pillar.
It was concluded that the car had been travelling 65 mph at the time of the crash, on a road whose speed limit is 30mph.
French police searched for CCTV cameras along the route to piece together what happened in the final moments before the crash.
Although there were cameras, no image of the Mercedes was recorded. Conspiracy theorists argue that there was CCTV recorded that night and that it suggests that the car was travelling at a far slower speed.
A photograph that has been presented to the BBC as proof of CCTV, turned out to be a photo taken by a paparazzi at the back of the Ritz Hotel before the couple departed.
In his summing up, coroner Scott-Baker, confirmed Henri Paul was driving at twice the speed limit when the accident happened, helping the jury pass a verdict that the speed of the Mercedes had contributed to the crash.
Was another car involved in the crash?
Two weeks after the accident, French police announced that the Mercedes had collided with another car shortly before losing control and crashing.
White scratches found on the right side of the Mercedes, as well as broken tail lights discovered at the scene of the accident, allowed forensic teams to prove that the car was a white Fiat Uno, made between 1983 and 1989.
Conspiracy theorists argue that the Fiat deliberately collided with the Mercedes to cause the crash that killed Princess Diana. They believed it was driven by James Andanson, who was in the pay of MI6.
He died two years later in what they claim was suspicious circumstances. But police called it suicide, pointing out that Andanson had an alibi and his white Fiat Uno was too dilapidated to drive the 175 miles from Andanson's country house to Paris.
The white Fiat Uno driver has never been identified but experts at the inquest said it would be almost impossible to engineer a crash, and Diana might have lived if she was wearing a seatbelt.
Along with the mystery Fiat Uno doubters believe there was a "massive flash" of light in the tunnel moments before the Mercedes crashed.
A man purporting himself to be a witness to the accident, Francois Levistre, told newspapers that he thought the Mercedes lost control after being "blinded" by a light.
Later Richard Tomlinson, the former MI6 officer, claimed that a similar method was suggested as part of a plan to assassinate former Serbian leader Slobodan Milosevic in 1992.
But during the inquest Richard Tomlinson backtracked on his claim under cross examination. And there was little support for the bright light theory, with numerous witnesses denying they saw a massive flash.
Eventually, even Al Fayed's lawyers agreed that the Fiat Uno was not a contributory cause of the crash. The driver has never been identified.
Why did it take so long to get Diana to hospital?
It took nearly two hours to get Princess Diana from the scene of the accident to La Pitie-Salpetriere Hospital, only four miles away.
In France, it is standard procedure to send an ambulance with a fully-equipped team of doctors and nurses to assess the victim's injuries and administer care immediately.
Diana's condition was unstable. She suffered two heart attacks, one while being removed from the wreckage of the car, and another while on the way to hospital.
The French authorities told The Conspiracy Files that her ambulance drove deliberately slowly to not further upset her injuries.
Conspiracy theorists argue that Princess Diana would have been saved if the ambulance had rushed her off to hospital.
They also point to the fact that Diana's ambulance passed five other hospitals along the way, including one reserved for VIPs.
But during the inquest the jury heard that the La Pitie-Salpetriere Hospital was chosen because of its expertise in chest trauma, which meant it had the best facilities to treat Diana.
Some expert witnesses, however, did suggest that Diana might have been saved if she had got to hospital quicker.
Was Diana engaged to Dodi?
Sceptics claim that Princess Diana was pregnant with Dodi's baby and that she was murdered to avoid causing trouble to the establishment.
Conspiracists point to the fact that the princess was embalmed in Paris, hours after the crash, before a full autopsy had taken place on her body.
Embalming is not only illegal in France, say the theorists, but the formaldehyde used in the process would have corrupted the results of a pregnancy test and given a false result.
Conspiracy theorists claim that the princess was also engaged to Dodi, and that the couple were about to announce their engagement.
Six hours before the crash, Dodi picked up a ring he had ordered from the "Dis-Moi Oui" (Tell Me Yes) range of Repossi's jewellers.
Princess Diana's close friends have contested the ring as proof of any engagement. Rosa Monckton told the Conspiracy Files that Dodi showered Diana with gifts, and that the ring he was going to give her was "going firmly on her right hand".
Ten days before she died, Princess Diana visited an acupuncture clinic in London for treatment of pre-menstrual tension.
Checks carried out by her consultant, Dr Lily Hua, confirmed that Diana was not pregnant.
Furthermore, the princess was only partially embalmed. French doctors say this was done at the request of her family, as the practice is illegal in France.
Partial embalming is a common procedure to preserve the body for aesthetic purposes and experts argue it would not corrupt pregnancy tests.
Was Diana's driver a secret agent?
Henri Paul, the driver of the Mercedes that killed Princess Diana and Dodi, was deputy head of security at the Ritz Hotel.
He had been providing back-up security for the couple on their last day in Paris, but left work at 7pm.
He returned to the Ritz three hours later, when Dodi and Diana arrived at the hotel to have dinner.
French police later discovered that Paul had a number of accounts in different banks across Paris, with balances in excess of his £21,000 ($42,000) salary.
Paul was also found to have over £1,200 ($2,400) on him the night he died. Furthermore, no one has been able to place the whereabouts of Paul between 7 and 10pm that night.
Conspiracy theorists claim that Paul was a secret service agent and that he was paid to murder Princess Diana and Dodi Al Fayed on the orders of the British Establishment.
This idea was ignited further when ex-MI6 agent Richard Tomlinson purported to have seen the file of a paid informant based at the Ritz.
Sceptics claimed this informant must have been Paul.
French police discovered that Henri Paul did have links with the Secret Services, but at a very low level.
They concluded that he did nothing more than inform on VIPs who were staying at the Ritz. There is no evidence to suggest Paul was working for MI6.
The was reiterated in the inquest, when the former head of MI6, Sir Richard Dearlove claimed that if Henri Paul had been working for MI6 there would have been a "P" file. Not only was there no "P" file for Henri Paul, but there was no "P" file for anyone working at the Ritz Hotel in Paris.
Did Diana predict her own death?
Ten months before she died, Diana wrote a letter in which she spoke of her fears of a plot to kill her in a road crash.
The note claimed the Prince of Wales was planning an accident in Diana's car, so he could then marry William and Harry's nanny Tiggy Legge-Bourke.
Shortly after the letter came to light, another note surfaced of a discussion Diana had had with her solicitor Lord Mischon. In the meeting with Mischon, Diana had said she thought efforts would be made to get rid of her, that the Queen would soon abdicate, and that Camilla Parker Bowles was under threat as well.
Conspiracy theorists seized on the two notes as evidence that Diana knew she was going to be murdered. They also accused the police of covering up the Mischon note by keeping it secret for six years.
It is an accusation the police fervently denied during the inquest which also heard evidence that the threats were in Diana's imagination and did not sum up her normal frame of mind. Much of the detail in the letters also turned out to be untrue, the Queen has not abdicated and the Prince of Wales has married Camilla Parker Bowles.
The Conspiracy Files: How Diana Died will be broadcast on Tuesday, 8 April at 1900BST on BBC Two.
This is an updated version of the original programme broadcast on Sunday, 10 December 2006.