Princess Diana's death has been surrounded by heartbreaking - and terrifying - theories which will be discussed in an upcoming documentary.

To mark the 25th year since her death, British TV network Channel 4 decided to launch a four-part series that would explore the stories and findings of two police investigations into her passing.

For what it's worth, the first investigation was conducted by French police in 1997, while the second and most recent one took place in 2004 under British authorities.

As quoted by Newsweek, Channel 4 revealed that the documentary would tell how the public, press, and internet created and fueled the theories surrounding Princess Diana's death.

"This utterly compelling series explores in forensic detail what happened in the investigations following the death of Princess Diana -what it was like for the detectives working on a huge global news story that was not just a tragedy for the families involved, but a massive internet phenomenon too," Channel 4 executive Shaminder Nahal said.

The project, which has the working title "Investigating Diana: Death in Paris," will air before or after the 25th anniversary of her death on August 31.

Princess Diana's Death Theories

Since Princess Diana's death became the most shocking event at that time, it led to conspiracy theories that suggested even the most unbelievable scenarios - including a buzz that she was pregnant at the time of her death and that Prince Charles killed her.

In 2005, Pierre Mutz and Sir John Stevens launched an investigation by talking with the Paris police HQ. At that time, Mutz asked his companion why the senior policeman in Britain started investigating a simple accident.

However, little did the Préfet de Police know, the Metropolitan Police Commissioner actually wanted to conduct the most important investigation yet. The probe, dubbed Operation Paget, was launched in pursuit of finding the answers surrounding Princess Diana's death.

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One of the theories involved the "mysterious Fiat Uno" that collided with her Mercedes before it crashed. The driver, bodybuilder Le Van Thanh, was only 22 when the tragic accident occurred. This time, he claimed he was never around the area in the early hours of August 31, 1997.

The three-year Operation Paget found out that Van Thanh was truly at the wheel when he bumped into the princess' car.

Meanwhile, Princess Diana's real-life chef sat down for an interview with The Post and discussed the statement about her car being tampered with to cause an accident. Darren McGrady recalled one instance where Princess Diana had second thoughts about driving herself alone.

"She joked: 'Watch the brakes, Darren. I think someone's been tampering with them,'" he disclosed.

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