Twenty-nine years after Princess Diana died in a car crash inside the Pont de l’Alma tunnel in Paris on August 31, 1997, two major documentaries — The Diana Investigations on Discovery+ and HBO Max, and HBO’s The Princess — have returned to the evidence with fresh eyes and, in some cases, the investigators who originally worked the case. What they found doesn’t close the story. In several ways, it makes the open questions harder to ignore.
The evidence that was buried, delayed, or mishandled
The detail that lands hardest in The Diana Investigations is the Mischon Note — a handwritten document taken by Diana’s lawyer, Lord Victor Mischon, during a private meeting in 1995. In it, Diana reportedly told Mischon she believed she would be killed in a staged car accident, specifically mentioning brake failure, to make way for Prince Charles to remarry. The note existed. Scotland Yard had it. French investigators from the Brigade Criminelle were not shown it until years after the crash — a delay that drew serious criticism and has never been satisfactorily explained by British authorities.
Then there’s the white Fiat Uno. Forensic evidence confirmed that a white Fiat made contact with Diana’s Mercedes in the tunnel just before the impact. French detectives traced thousands of matching vehicles across Paris and came close — identifying a driver named Le Van Thanh, who was interviewed. He was never publicly charged. He was never fully cleared by British authorities either. That gap, documented on camera by the investigators themselves in the series, is the kind of thing that keeps conspiracy theories alive not because of wild speculation but because the official record simply doesn’t close it.
One theory the documentary does shut down: the claim that Henri Paul‘s blood samples — the ones that showed a blood alcohol level well above the legal limit — were swapped or contaminated after the crash. Cross-referencing carbon monoxide levels with DNA testing, investigators confirmed definitively that the samples belonged to Paul. The “swapped sample” version was a dead end, and the series is clear about that without softening what it means: the driver of Diana’s car was dangerously drunk.
How Martin Bashir and the media machine fit into the picture
The Diana Investigations makes an argument that goes beyond forensics: that Martin Bashir‘s manipulation of Diana in the lead-up to her 1995 BBC Panorama interview directly shaped her mental state in her final years. Bashir, a BBC journalist later found by an independent inquiry to have used fabricated bank statements to gain Diana’s trust, fed her suspicions about the people around her. The docuseries argues that this amplified her distrust of security personnel and official figures — a distrust she carried into 1997.
HBO’s The Princess takes a completely different approach and arrives at a different kind of conclusion. Built entirely from archival news footage and crowd audio — no talking heads, no reconstructions — it builds the case that the crash was the endpoint of a system, not a single act. The 1990s tabloid media machine, fed by public appetite for Diana’s image at any cost, created the conditions for the high-speed pursuit through the tunnel. The paparazzi chasing her car that night weren’t operating in a vacuum; they were responding to demand. The film makes the audience sit with that discomfort rather than offering them a clean villain, which is either its strength or its limitation depending on what you’re looking for. Much like the way The Crown reimagined Diana’s final years, the most honest documentaries about her death leave you with more weight than resolution.
What both productions share is the recognition that the institutions surrounding Diana — the palace, the press, the police — were never fully accountable for the way they handled her life or her death. 29 years later, that accountability hasn’t arrived. The documentaries keep coming because the story keeps refusing to be finished.
