Just after midnight on August 31, 1997, the entrance to the Hôtel Ritz Paris was a chaotic scene. A crowd of around 30 photographers, known as paparazzi, had gathered, their camera flashes creating a constant, blinding strobe effect. Inside, Diana, Princess of Wales, and her companion, Dodi Fayed, were finishing a private dinner. The couple had arrived in Paris earlier that day after a holiday in the South of France, and the media attention had been relentless.

To avoid the throng, they devised a plan. A decoy car, identical to the one they'd been using, would depart from the hotel's main entrance on Place Vendôme. The hope was that the paparazzi would chase it, allowing Diana and Dodi to slip away quietly from a rear exit.

At approximately 12:20 AM, the plan was set in motion. While the decoy car sped off from the front, Diana and Dodi exited through the hotel's rear entrance on Rue Cambon. They climbed into a black Mercedes S280, driven by Henri Paul, the Ritz's deputy head of security. Trevor Rees-Jones, a bodyguard and former paratrooper, sat in the front passenger seat.

The ruse failed. Several photographers on motorcycles had anticipated the move or were tipped off, and they immediately spotted the Mercedes as it pulled away. The pursuit began instantly.

The short journey was meant to take them to Fayed's private apartment near the Arc de Triomphe, a drive that should have been simple. Instead, it became a high-speed chase through the streets of Paris. Paul accelerated aggressively, attempting to outrun the pursuing motorcycles. The car sped along the north bank of the River Seine, past the Louvre, and towards the Place de l'Alma.

At 12:23 AM, just three minutes after leaving the hotel, the Mercedes entered the Pont de l'Alma tunnel at an estimated speed of 105 km/h (around 65 mph). The speed limit in the tunnel was 50 km/h (31 mph). As the road dipped and curved slightly to the left, Paul lost control of the vehicle. The car clipped a Fiat Uno, swerved violently, and slammed head-on into the tunnel's 13th concrete support pillar. The impact was catastrophic, spinning the car around before it came to a halt.

The wreckage of the Mercedes was a scene of devastation. The first people to arrive were the very photographers the group had been trying to escape. Within minutes, emergency services were on the scene. Dr. Frederic Mailliez, an off-duty doctor who happened to be driving through the tunnel in the opposite direction, was the first medical professional to provide aid.

Henri Paul and Dodi Fayed were pronounced dead at the scene. Trevor Rees-Jones, the only one wearing a seatbelt, was conscious but had suffered severe facial injuries. Diana was alive but critically injured, having been thrown from her seat on impact. The initial triage began in the darkness of the tunnel, marking the start of a desperate but ultimately futile effort to save her life.

The events of that night unfolded with shocking speed, a tragic sequence of decisions and circumstances that culminated in a global moment of mourning.