Grunewald, who directed the documentary, shared additional insights into the project exclusively with Express.co.uk earlier this year. She emphasised that the film investigates some of the most controversial moments in recent royal history.

“Harry – The Lost Prince will look into one of the most heartbreaking periods of the Royal Family since the abdication of Edward VIII in 1936,” said Grunewald.

She added that damaging revelations about the monarchy stem directly from the Sussexes themselves: “The most damaging allegations can only come from within. Revelations that shock the Royal Family only come out of Prince Harry‘s or Meghan Markle‘s mouths.”

The documentary also scrutinises Meghan Markle’s evolving reputation.

“She [Meghan] might be embarrassed about the amount of criticism she now gets even in communities that used to back her after the decision to leave the Royal Family as a working member,” Grunewald said.

She noted that some individuals involved with Prince Harry’s Invictus Games have questioned Meghan’s role and attitude, while others remain hopeful about the couple’s potential.

“At the moment it is hard to see any big achievement of their Archewell Foundation, which claims to work for the improvement of communities. But there are still voices who see the high potential of the couple not only for the British monarchy but also for a liberal society.”

The documentary also addresses Meghan’s efforts to discuss racism and her experiences within the Royal Family in the context of American political debates.

Grunewald reflected on the late Queen’s perspective, saying: “I begin to understand the late Queen’s verdict that you can’t be ‘half in and half out.’”

Grunewald and her team conducted extensive research for the project, filming in California, where Harry and Meghan live with their children, Prince Archie, five, and Princess Lilibet, three.

They also travelled to New York to speak with sources close to the Sussexes.

The team behind ‘Harry – The Lost Prince’ is known for uncovering secrets about the British Royal Family, having previously aired a special on ‘Princess Kate and The Drama of the Windsors’.