Elizabeth Debicki says the pressure and "immense responsibility" of portraying Princess Diana's final days in 'The Crown' "woke us up in the night".
The 33-year-old actress plays the late royal - who died in a car crash in Paris in 1997 aged 36 – during the weeks leading up to her tragic death and following her split from husband Prince Charles, and she says they took a huge amount of care when tackling the sensitive scenes.
Asked how seriously they approached the subject matter, she told 'Entertainment Tonight': "An immense, immense responsibility.
"It's difficult to describe, it was something that we thought about, that we carried with us, that woke us up in the night."
She continued: "We tried our very best to do [the story] properly."
Elizabeth hopes season six provides viewers with "what they need from it".
She said: "My message is just - thank you for sticking with the show, thank you for watching it. I hope that we give you what you need from it."
The job of playing Diana was both "very beautiful" and "very harrowing".
She added: "It was a very difficult and also very beautiful thing to be asked to do as an actor. So as much as it was very harrowing, it was also -- there was a sort of grace to it at the same time."
Elizabeth's latest comments come after she admitted she was "very scared" filming the late Princess Diana's swimsuit scene.
The royal was snapped by paparazzi a week before her death sitting on the end of the diving board of her boyfriend Dodi Al Fayed's father Mohamed Al-Fayed’s private yacht Jonikal off the coast of Portofino in a striking blue swimsuit.
And much like filming her "revenge dress" look, a silk Christina Stambolian gown, that Diana donned to a bash at the Serpentine Gallery in Kensington Gardens after Charles confessed to having an affair, Elizabeth didn't know what to expect "emotionally" and physically until she was in the moment.
She said in a promotional video: "There was just something about that swimsuit and recreating that moment that felt very sacred.
"It was very important we got it right. In a way, it reminded me a little bit of when we shot the revenge dress - it's as close as possible to the real imagery."
Elizabeth continued: "As an actress, I get to enter into that space and discover what's emotionally in that moment. With the revenge dress, I didn't really know until I stepped out of the car.
"At this moment, I didn't really know until I was sat with the sea under me."
Elsewhere, Elizabeth said she found it "completely unbearable" filming "horrendous" scenes of Diana and Dodi (Khalid Abdalla) being chased by paparazzi
She added: “There’s nowhere you can go and you only have to be in a situation like that for about a minute before you realise, ‘This is completely unbearable’.
“To have this swarm around you, you feel very trapped. It’s a really unpleasant experience.
“There are times as an actor — where you’re actually doing a stunt, or you’re jumping off a building, or you jump into the water, or whatever it is — that you experience something very physical and there’s not a huge amount of acting that takes place.
“I think that was what was happening a lot when we were recreating those scenes, because it’s really horrendous to have that many people yelling at you and wanting something.”
The last six episodes of 'The Crown' will arrive on December 14 on Netflix.
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