Princess Diana, undoubtedly the most loved woman, died after suffering fatal injuries in a car crash in Paris on the night of August 31st 1997.
Though her death led to a string of controversies, it is seen as the most important event in the country, according to a British poll held in 2002.
Diana, her then boyfriend 41-year-old Dodi Fayed, son of Egyptian billionaire Mohamed Al-Fayed, the former owner of Harrods department store, and driver Henri Paul, all died on that fateful night. Her bodyguard Trevor Rees-Jones was the only one who survived.
The year 2017 marks the 20th anniversary of the death of the People's Princess as she was popularly known.
The investigations carried out by the French and British officials later concluded that the driver Henri Paul, was allegedly drunk and responsible for the crash. He was on anti-depressants when he lost control of the car as it sped through the tunnel, in an attempt to avoid a group of paparazzi chasing Diana and Fayed. Tests later showed Paul was three times over the drink-drive limit.
When all went dark in the tunnel
On August 30, 1997, Diana left Sardinia on a private jet and arrived in Paris with Dodi Fayed. The two had intended to stay there for the night.
Henri Paul, the deputy head of security at the Ritz Hotel was instructed to drive the hired Mercedes-Benz to get away from the paparazzi.
Diana and Fayed then left from the hotel's back entrance at around 00:20 on 31 August, heading for an apartment in Rue Arsène Houssaye.
They were the rear passengers; Trevor Rees-Jones, member of the Fayed family's personal protection team, was in the front passenger seat.
After leaving the rue Cambon, they drove along Cours la Reine and Cours Albert 1er – the embankment road along the bank of the River Seine – into the Place de l'Alma underpass.
Reports indicate that at around 12:23 am, at the entrance to the tunnel, Paul lost control; the car turned to the left of the two-lane carriageway before colliding head-on with the 13th pillar at an estimated speed of 105 km/h.
The car then spun and hit the stone wall of the tunnel backwards, finally coming to a screeching stop.
The impact reportedly caused substantial damage, particularly to the front half of the vehicle, as there was no guard rail between the pillars to prevent this.
Diana suffered a cardiac arrest after she was removed from the wrecked car. She was brought to the Pitié-Salpêtrière Hospital where she breathed her last despite multiple attempts to save her.
According to a report in Telegraph on May 31 this year, the Mercedes that Princess Diana died in Paris was a "death trap that had been written off but was later rebuilt and put back on the road".
The shocking claim was made in a new TV documentary Death Of Diana: The Incredible Revelation.” The accompanying book Who Killed Lady Di? and the documentary were released in the run-up to the 20th anniversary of her August 31, 1997 death.
A previous accident had allegedly taken place two years before Diana's death when a prisoner out on remand stole the vehicle and took it for a ride.
Those are the facts. Now, here are some famous conspiracy theories surrounding Lady Di's death.
Car mishap ordered by Diana's family
One of the most popular theories suggest that Diana was carrying Dodi's child and the couple were about to get engaged. Since the Royal family could not bear the inevitable scandal, one of the conclusions drawn is that Diana's death was ordered by her own kin.
Involvement of MI6
Richard Tomlinson, a former MI6 agent, was dismissed from the intelligence services and later served time in prison for breaching the Official Secrets Act 1989. Rumours have it that Tomlinson alleged that agents had been monitoring Diana and that her death mirrored plans which he had seen in 1992 for the assassination of the President of Serbia. An inquiry was launched which eventually concluded that Tomlinson's claims were no less than an exaggeration.
Throughout the inquest that was carried out in 2008, Mr Fayed, maintained that Diana and Dodi were "murdered" by MI6 on the orders of the Duke of Edinburgh (Prince Philip, the Queen's husband and Prince Charles' father).
Mysterious white Fiat Uno
An analysis of the wreckage showed that the Mercedes had come in contact with a white Fiat Uno, leaving traces of paint on the Mercedes bodywork. It was alleged that the vehicle was used by the "security services" to block the road in front of the Mercedes, causing it to crash into the side of the tunnel. The Fiat Uno was allegedly never found.
The missing CCTV images
Mr Fayed in 2003 claimed that there were about 10 cameras on the route that was taken by Diana and Dodi that night, including one on the entrance to the tunnel itself. However, there are no recordings from any of these for the night in question.
Role of Henri Paul under scanner
Though he died instantly in the accident, which concludes that he may not be behind the crash, conspiracy theorists say that Paul was employed by the national security service. The evidence that led to this is the fact that Paul had a lot of cash on him during the time of the accident.
Diana's death was met with an extraordinary expressions of grief from the public. According to reports, her funeral at Westminster Abbey on 6 September 1997 drew an estimated 3 million mourners and onlookers in London.
The event had a worldwide television coverage in 200 countries and in 44 languages watched by 2.5 billion people.