Royal Family's strategy under huge pressure after barrage of ruthless attacks - analysis by Cameron Walker

But one review, published in the centre-left Independent newspaper, has described his work as "unfailingly sympathetic to the Sussexes".

They did, however, describe Omid's book as "pacy" and "well written".

WATCH HERE: ‘This is pure nastiness’ says Royal expert on new book Endgame

The royal biographer, branded Meghan Markle's cheerleader by some (a description he denies), alleges the Princess of Wales is "terrified of doing anything other than grinning photo-ops" and Princess Anne persuaded the King to evict the Duke and Duchess of Sussex from their UK home, Frogmore Cottage.

After the infamous Oprah Winfrey interview (Prince Harry accused his father of financially cutting him off and Meghan accused an unnamed member of the royal family of questioning what colour her unborn child's skin would be) Buckingham Palace released a statement which said: "recollections may vary".

So why are the royals not fighting back this time?

The mystery surrounding the House of Windsor is, arguably, part of the appeal for the wider public - who buy into the pomp, pageantry and patriotism associated with the monarchy.

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But there is clearly a desire for the veil of secrets to, on occasion, be cast aside.

Prince Harry's sensational memoir, Spare, lifted the lid on his life growing up inside the Royal Household and became the fastest-selling non-fiction book of all time.

The Duke of Sussex was criticised for publicly attacking his own family, resulting in opinion polls on both sides of the Atlantic showing a slump in his popularity.

Newspapers also appear to thrive off increased coverage of the private lives of the Royal Family, with the public eager to know every detail.

But Prince Harry and Meghan spoke to the King on the phone to wish him a happy 75th birthday a couple of weeks ago, according to a source close to them, suggesting a mend in relations could be on the cards.

Will Omid Scobie's latest book "Endgame" help with this healing of relations? I doubt it.

In 'Endgame', most working members of the Royal Family are exposed to a cannon fodder of criticism, but Harry and Meghan appear to avoid any allegations of wrongdoing.

Prince William, I suspect, will be particularly frustrated about what royal journalist Robert Jobson has dubbed a "character assassination" of his wife, the Princess of Wales.

Still, Kensington Palace remains silent - taking the lead from Buckingham Palace.

Is this strategy working? It appears to be so far.

The working royals have kept a dignified silence after every bombshell hurled from team Sussex in recent years, including the Netflix series and Harry's memoir, "Spare".

But opinion polls consistently show that working royal's popularity either increases or stays the same.

This is in contrast to Harry and Meghan's, whose popularity appears to be suffering in the United Kingdom and the United States.

Let's not forget that the Prince of Wales is the most popular public figure to unite America, according to a recent Gallup poll, and has been dubbed a "global statesman".

What about Archewell Communications, Prince Harry and Meghan's PR Machine?

Officially, they appear to be distancing themselves from Omid Scobie's latest book and have not commented.

However, Omid Scobie has publicly acknowledged he shares mutual friends with Meghan Markle who, in my view, would not have spoken to Omid without Meghan's permission.

Meghan apologised to the High Court in London in 2021 for forgetting she instructed an aide to brief Omid Scobie and his co-author, Carolyn Durand, to help with another book "Finding Freedom", a sympathetic view of Harry and Meghan's exit from the working royal family.

Earlier this year, Meghan signed with the prestigious Hollywood agency, WME, to "focus on building Meghan's global enterprise" according to Variety.

If Meghan's PR experts are driven by opinion polls, they may be advising her to stop painting herself as a victim, and focus on more positive philanthropic and business projects.