Diana: Her True Story was published in 1992 and revealed the royal family member’s profound unhappiness.

“I came to this character with a pretty blank canvas,” the actress says.

Then eventually you have to just throw it all away and do the scene."

The Crown Season 5

Elizabeth Debicki as Princess Diana in ‘The Crown’.Netflix

I found it to be a really rich experience and a real challenge as well.

“I mean, I don’t say this very often, but I was shaken.”

Season 5 ofThe Crownis streaming now on Netflix.

Andrew Morton and the cover of his 1992 book Diana: Her True Story. ; BARCELONA, SPAIN - APRIL 23: Writer Andrew Morton poses during Sant Jordi day celebrations on April 23, 2013 in Barcelona, Spain. Sant Jordi is a Catalan holiday and is similiar to Valentines day, but during the day roses and books are exchanged between loved ones and collegues. (Photo by Robert Marquardt/Getty Images)

‘Diana: Her True Story – in Her Own Words’; its author, Andrew Morton.Amazon; Robert Marquardt/Getty