What's the story?

Diana: The Interview That Shocked The World.

Tell me more.

It is 25 years since the landmark TV moment when Diana, Princess of Wales was interviewed by Panorama reporter Martin Bashir, in which she shared candid details about her marriage to Prince Charles and royal life.

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A reminder, please.

Among the bombshell revelations was Diana's statement that, "there were three of us in this marriage, so it was a bit crowded," referring to the Duchess of Cornwall (then Camilla Parker Bowles). She also spoke openly about postnatal depression and her struggle with bulimia.

Ah, yes. Why do you bring it up?

A new 90-minute documentary, due to air on Channel 5, sets out to uncover why Diana chose to take such an extraordinary gamble and reveals how Bashir – then a relatively unknown name – came to gain her trust.

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That sounds intriguing.

Indeed. The film challenges viewers to see Diana afresh, examining how her Panorama interview shifted attitudes toward the monarchy and our treatment of women in the public eye. There are interviews with erstwhile butler Paul Burrell, former BBC royal correspondent Jennie Bond and body language expert Judi James.

When can I watch?

Diana: The Interview That Shocked The World is on Channel 5, October 11, at 9pm.