With the new season of The Crown finally here, insiders say Princess Anne is struggling to keep her cool composure over the show's inevitable retelling of the night she was nearly kidnapped in 1974.
"There's no way the TV series will avoid this incident because it changed the royal family for years," spills a palace insider. "Four people were shot trying to protect Anne and they very nearly failed, because they didn't have any back-up.
"It won't be easy for Anne to see this being recreated for entertainment. She might be the queen of calm, but that night back in '74 is the only thing that still rattles her cage."
On March 20, 1974, around 8pm, Princess Anne and her new husband, Mark Phillips, were being chauffeur-driven towards Buckingham Palace in the back of a Rolls-Royce limousine with her special ops bodyguard and her lady-in-waiting.
Driving down the famous Mall, which leads up to the front of the palace, a rented Ford Escort overtook them and forced them to stop. When the Princess' bodyguard stepped out to meet the man exiting his car, he was shot in the shoulder.
With bullets flying through her back window, Anne's chauffeur was shot and slumped down in his seat.
The Princess herself, now 69, later recalled in an interview with TV host Michael Parkinson that she had a "discussion" with the gunman, refusing to go with him and denying she had the £2 million (equal to £15 million today) he was demanding.
By that time a man in a passing taxi stopped and tried to intervene, but he too was shot.
Finally, a policeman arrived and managed to call for back-up, despite also being shot.
Another passer-by, this time a former boxer, intervened, and thanks to brave Anne's quick thinking by exiting the car on the other side and distracting him, her would-be kidnapper found himself cornered by police.
He was soon caught in a nearby park and later revealed to be 26-year-old Ian Ball, a mental illness sufferer from North London.
The incident was said to have a huge impact on the Princess for years to come.
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"She might have got on with her royal duties the very next day, but mark my words, she will never get over that night," another palace source tells.
"She's vowed to not watch any episode featuring that horrible moment in her life. It will be bad enough having half the world talking about it the day after it airs."
The Crown, Season 3 is now on Netflix.