The Princess director on why it's different to to other Diana docs

"I think Diana's story is probably one of the most told and retold stories in the last few decades," he said. "And there [have] been endless documentaries and drama films and podcasts and books out there.

Perkins, who also directed documentary Tell Me Who I Am, explained his emphasis on making a film which offered a fresh perspective.

"We felt it was really important to only make another documentary if we thought we had something new to say or a new perspective to offer up," he said.

"My sense was that a lot of the documentaries that have been made about Diana were consciously kind of interior – they were trying to get inside Diana's head, often successfully, but they're trying to kind of work out how she was feeling, trying to understand her psyche or what made her tick or what was motivating certain decisions.

"All of that is interesting but inevitably does involve a degree of speculation because, of course, we can't be sure how she was feeling," he continued. "And so I felt that, for our film, the more interesting thing about Diana's story was not necessarily what it said about her, but actually what it says about all of us.

"And so the thing that really formally makes our film different is that traditionally documentaries like this will be made by interviewing people that new Diana or experts, and they will be telling us from a position of hindsight what happened 25 years ago.

"We don't have anything any headshot interviews in our film at all," the director said. "Our entire film is built just out of archive from the time itself. And my hope is that that archive-only approach sort of allows us to take you back in time – almost like a time machine or a time capsule.

"It takes you back into the 1980s or 1990s and doesn't let you escape and hopefully also forces us to turn the camera back onto all of us.

"So yes, the film is about Diana, but actually what I'm interested in is exploring us and our reaction to the story and I want the film to ask some complex but important questions about, yes, our relationship to Diana, but actually more broadly our relationship to monarchy, and our relationship to celebrity and celebrity culture, which obviously continues to evolve today.

Perkins said the most important thing for him was the documentary's ultimate question: "What was our role in this story? What was our complicity, for want of a better word, in this tragic tale?"

Additional reporting by Grace Henry.

The Princess arrives on Sky Documentaries on Sunday 14th August. Read more of our Documentaries coverage or visit our TV Guide to see what else is on.

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