Harry and Meghan's new Netflix documentary has been described as "utterly explosive" and could be damaging to the Royal Family.
Set to arrive on the streaming site on December 8, the six-part series delves into their lives before and after they stepped down as working royals in 2020.
The trailer was released earlier this week, showing black and white clips of the couple's life and memories such as their wedding day. The bombshell series is for the public to see "what's happening behind closed doors", as Harry has said.
One source in contact with a Netflix production insider told the Mirror : “I genuinely think it’s going to be worse than the royals can imagine.
“I’m told that it’s going to be utterly explosive and will be very damaging.”
The trailer was released while the Prince and Princess of Wales were on a three-day trip to Boston ahead of the Earthshot prize.
In black and white clips, intimate moments between Harry, 38, and Meghan, 41, are shared – from the pair kissing on the kitchen counter and joking around in California, to new footage of their wedding day.
It also shows a crying Meghan on the phone and a picture of the Princess of Wales looking stern, suggesting she may not come across well in the series.
“No one sees what’s happening behind closed doors,” says Prince Harry, who then brings children Archie, three, and Lilibet, one, into the mix with: “I had to do everything I could to protect my family.”
And Meghan adds at the end: “When the stakes were this high, doesn’t it make more sense to hear our story from us?”
Royal experts have called the timing of the trailer a "declaration of war" and said it could either create support for the Sussexes, or widespread hatred.
The source continued: “A lot of people are either pro-Sussex or pro-William and Kate, but there’s a belief that this documentary will bring people onside with Harry and Meghan. The big question is that, whatever the revelations are, who will people side with after seeing the show. It has that feeling like the public will have to choose.
“Whatever comes out, some people will think that Harry is betraying his family and that it’s unforgiveable. But if what finally airs is as seismic as we’re led to believe then it may be good for the Sussexes.
“There’s been some talk the documentary has been toned down but at the moment that’s wrong.”
Prince William is expected to talk to his father King Charles about the upcoming documentary, with the two men expected to put on a "united front".
Senior palace officials working for the King and Prince of Wales will watch the first three episodes going out on Thursday to ensure swift action can be taken if needed.
Meanwhile, Prince Harry appeared in a video dressed as Spiderman for the charity Scotty's Little Soldiers this week.
The charity supports children who have lost parents as they served in the Forces. Harry, who lost his mother Diana when he was 12, said that although it's normal to miss people at Christmas you should still "have fun".
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