The Crown 's Elizabeth Debicki says recreating Princess Diana's recordings for her biography was a 'challenge'

In preparing to portray Princess Diana on the '90s-set fifth season of The Crown, Elizabeth Debicki relied on both series creator Peter Morgan's scripts and materials sent to the actress from the show's research department.

"I came to this character with a pretty blank canvas," the actress says. "I'm Australian, shock-horror, and I was very young during this period of history, so I didn't have any lived memory of it. What I learned, I learned through Peter's interpretation and then the research archive department that assists in building a very solid foundation of the actual historical events. Then eventually you have to just throw it all away and do the scene."

Netflix Elizabeth Debicki as Princess Diana in 'The Crown'

Debicki had plenty of archival material to mull over before shooting episode 2, which is directed by Jessica Hobbs and details how Diana helped author Andrew Morton write his biography of her, Diana: Her True Story. As depicted on the show, Diana declined to let Morton interview her, instead recording lengthy answers to the writer's questions at her Kensington Palace home, with her friend Dr. James Colthurst serving as a go-between.

Diana: Her True Story became a publishing sensation, was translated into 29 languages, and reportedly sold five million copies around the world. Morton's work effectively signaled the end of the royal marriage, and in December 1992, Prime Minister John Major announced that Diana and Prince Charles had separated.

In October 1997, just two months after the princess' death in a Paris car crash, Morton published a new edition of the book titled Diana: Her True Story in Her Own Words. This time, the author made clear that Diana had been the principal source for the original book and included edited transcripts of the princess' taped responses to his questions. In 2004, NBC screened a documentary titled Princess Diana: The Secret Tapes, which featured excerpts from the recordings Diana made for Morton, who was a consultant on season 5 of The Crown.

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

Debicki describes recreating this chapter of Diana's story as "a fascinating and complex task," adding, "It's extremely unusual that you would just suddenly have this portal opened up where you can access that kind of reality, and that emotional truth, of your character, and then find ways to reinterpret it as an actor. I found it to be a really rich experience and a real challenge as well. I recently watched that episode, and I feel the way Jess Hobbs directed it brings all the pieces together in this really satisfying way."

Morton, who is played by Andrew Steele (Outlander) in the episode, has given Debicki's performance as Diana a thumbs-up. "It left me breathless, and it took me back all those years," Morton said in a Good Morning America interview on Friday. "I mean, I don't say this very often, but I was shaken."

Season 5 of The Crown is streaming now on Netflix.

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