Directed by British actor-filmmaker Keith Allen, the film was set to open Aug. 31 in the United States, Spain, Italy, Holland, Brazil, India and Russia, in time for the 15th anniversary of the princess' death in a Paris car crash at the age of 36.
Also killed in the high-speed, drunk-driving wreck was her boyfriend Dodi al-Fayed, whose father, billionaire Mohamed al-Fayed, financed "Unlawful Killing," a film that criticizes the British royal family and suggests there was a coverup surrounding Diana's and Dodi's deaths even though the allegation was proven false in court. It was determined the couple's driver, Henri Paul, who was also killed in the crash, was intoxicated and driving recklessly at the time.
The Hollywood Reporter said producers won't release the film in theaters as scheduled because they couldn't secure the necessary insurance to indemnify them and distributors from lawsuits pertaining to the film's content.
"It became undoable. We are all disappointed," producer Conor Nolan told the entertainment industry trade newspaper. "We worked on 'Unlawful Killing' for four years. We've written back to all of the distributors and are returning their minimum guarantees. We're doing the decent thing."
The Hollywood Reporter said the filmmakers were told they would have to make 87 cuts for the documentary to be shown in the United Kingdom, so no theatrical release or television broadcast is scheduled there.
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