The new episodes of the Netflix hit, released later this month, will see the introduction of a young Camilla, whose maiden name was Shand, as she becomes romantically involved with the heir to the throne.
However, experts have criticised scenes that depict Lord Mountbatten and the Queen Mother forcibly splitting the pair up.
The storyline sees Prince Charles (Josh O’Connor) tell his great uncle Lord Mountbatten (Charles Dance) that Shand (Emerald Fennell) is “the one”. Mountbatten then hatches a plan with the Queen Mother (Marion Bailey) to separate the pair for good, with the former organising an eight-month posting overseas to “bring [Charles] to his senses”, while leaving the Queen Mother to keep Shand and Andrew Parker Bowles on course for marriage.
Queen Elizabeth II then calls upon her mother and Lord Mountbatten to explain themselves, saying: “What if it is love? Shouldn't it be allowed to run its course? I was allowed to marry my choice.”
To this, the Queen Mother responds that the system is too fragile to allow for “unpredictable” and “dangerous” elements.
Penny Junor, who has written biographies of both Prince Charles and the Duchess of Cornwall, told The Telegraph the storyline was a clear use of “dramatic licence” that could “cause a lot of damage”.
Junor said the Duchess was “potty” about Parker Bowles when she met Prince Charles.
“He was a commanding officer, Charles was very much a work in progress at that point, there was no competition between the two men,” she said, adding that Parker Bowles had repeatedly cheated on the then Shand.
She said it was unlikely that Lord Mountbatten had arranged for him to be posted abroad.
“He had joined the Navy, he was assigned to a ship and that ship was going to the Caribbean,” she said. “I have never heard (such a plot) suggested at all.”
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The author said the storyline appeared to be “dramatic licence”, adding; “That’s what terrifies me about the whole series. It can do a lot of damage.”
Last week, it emerged that Prince Charles’s aides are believed to be “paranoid” about the portrayal of his affair with the Duchess of Cornwall in the show.
On his responsibility to portray events accurately, The Crown writer Peter Morgan has previously said: "I feel the responsibility of that, and whether I'm misjudging it, or whether I've oversimplified it, or whether my version – which I'm happy to say is just me having a punt, I'm just guessing – gets taken too seriously, [because] I don't want to be part of creating bogus history."
The Crown season three will be released on Netflix on 17 November.
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