Elizabeth Debicki on Queen Elizabeth's Death and What Surprised Her Most About Princess Diana (Exclusive)

Elizabeth Debicki takes her final bow as Princess Diana in season 6 of The Crown, concluding the series a year after Queen Elizabeth’s death.

Speaking to PEOPLE ahead of the show's season 6, part 1 premiere on Thursday, Debicki, 33, says that Netflix’s hit drama inspired by the lives of the British royals drew a new “empathy” for the family since its debut in 2016.

“It’s been a long journey people have had with the show, and I think it's one of the beautiful things The Crown has been able to do, is open up in this imaginary way, the very private lives of these public figures and create this huge empathy, I think, for the audience to experience in regards to characters that you may not have known so much about before,” Debicki exclusively tells PEOPLE.

“I'll say personally, the loss of the Queen was an enormous sadness. She was a pinnacle, and I think she's much missed and much loved in my adopted country and around the world as well,” adds the Australian actress of Queen Elizabeth's death. “So everybody's intention has always been to sort of tell the stories as authentically as we can and make these people as human as possible, make the characters as human as possible.”

The Crown paused production when the monarch died at age 96 in September 2022, and showrunner Peter Morgan told Variety he was then compelled to change the show’s ending.

The cast famously changed every two seasons to reflect the royals aging through the decades. Debicki plays the Princess of Wales in seasons 5 and 6, closing the role originated by Emma Corrin in season 3. Netflix announced in 2020 that Debicki would portray Diana in seasons 5 and 6, and the star says she put much into the study of the People’s Princess.

“I came into this experience of playing the role very naive. I didn't know a lot. I kind of had a kind of imprint in terms of who this person was, and I always imagined her as just this kind of extraordinarily beautiful princess and humanitarian figure,” says Debicki, who was 7 when Diana died.

The Crown alludes to the tragedy in the latest installment, though the moment of impact is not shown — a turn previously confirmed by PEOPLE.

On Aug. 31, 1997, the Princess of Wales and love interest Dodi Fayed were traveling by car in Paris with a driver and a bodyguard. The four were pursued by paparazzi when their vehicle slammed into a support column of the Pont de l'Alma tunnel, flipped and came to a rest in front of oncoming traffic. Dodi and the driver died instantly, while Diana died a few hours later.

Twenty-six years later, Debicki tells PEOPLE that the weight of playing Diana for the major streaming series was not lost on her.

“I did a lot of research for this role. I probably spent about a year doing research and that just filled in all these pieces and made me have such deep, deep respect and love for this person who I didn't know so much about. The battle that she went through in terms of media, public perception. I didn't know things about the divorce and how difficult all of that was for everybody in the family,” she says.

According to the actress, one thing she was delighted to discover was Princess Diana’s sense of fun.

“One of the things that surprised me that I loved finding out is that she had this kind of really wonderful, very cheeky sense of humor, that she was just so warm and human with people. That’s what she was so loved for, and it was so needed, too,” Debicki says of the royal rebel.  

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“She was a real groundbreaker in terms of her ability to move through perceptions or stigmas and really just use herself as the vessel to enact huge humanitarian change. She was prolific in that and she gave us so much. I was constantly surprised at how far she was moving the needle, whether it was talking about mental health issues, AIDS or landmines," she says of Diana's lasting legacy. "When we lost her, the world lost a woman who could create amazing change on a humanitarian level as well.”

The show closes with the premiere of part 2 on Dec. 14, told in six episodes. The last saga is expected to conclude multiple storylines, from Queen Elizabeth (Imelda Staunton) mulling the future of the monarchy, then-Prince Charles (Dominic West) and Camilla (Olivia Williams) taking the next step in their relationship while Prince William (Ed McVey) falls for classmate Kate Middleton (Meg Bellamy) at college.

The Crown season 6, part 1, is now streaming on Netflix.