Princess Diana biographer Andrew Morton praised Elizabeth Debicki’s performance The crown who was “shaken” by the late royal’s on-the-spot performance. During an interview with Good morning Americasaid Morton, “It took my breath away, and it took me back all these years,” adding, “I mean, I don’t say this very often, but I was shaken.” Morton wrote his biography Diana: Her True Story with the princess in 1992. The book spilled the beans on the late monarch’s unhappiness with her unfaithful husband Prince Charles, her battle with bulimia and feelings of emptiness and depression. Diana: Her True Story became a worldwide success and was translated into more than 20 languages. And reportedly around five million copies were sold worldwide. Speaking of further GMAthe 69-year-old said he was unaware of Diana’s desperate state of mind when he started the book. “What I didn’t realize at the time was her sense of isolation, her sense of despair within the royal system,” he added. Morton also acted as a consultant in its 5th season The crown. “The writers had asked me all kinds of questions like, what color was the wallpaper in my daughter’s bedroom, because that’s where I had a desk for a while,” she said. GMA.