Kristen Stewart's thoughts on playing Princess Diana in 'Spencer' laid bare

Kristen Stewart revealed unfiltered thoughts on how she prepared for the role of Princess Diana.

In historical movie Spencer, Stewart essays the late Princess as she comes to terms with her and Prince Charles' failed marriage.

“I took more pleasure in my physicality making this movie than I have on anything,” Stewart said on Friday at the Venice Film Festival. "I felt more free and alive and able to move — and taller, even.”

The Twilight star said that her curtsy “went out the window as soon as I stepped on set” of Spencer, but luckily there were royal advisers around to teach her the many different mannerisms that an “outsider” wouldn’t usually know.

“Once I learned the curtsy and learned we’re not supposed to go in the kitchen ourselves and steal food, all those details, I don’t really remember them,” she added. “But there was always someone to make sure we weren’t going out of line and [we were] staying authentic."

Talking about how much she learned about Diana, Stewart revealed, “I look at her, the pictures and fleeting video clips, and I feel [like] the ground shakes and you don’t know what’s going to happen.

“[She] sticks out like a sparkly house on fire. … There are some people endowed with an undeniable, penetrating energy. The really sad thing about her is that as normal and casual and disarming in her air [as she was] immediately she also felt so isolated and lonely. She made everyone else feel accompanied and bolstered by this light and all she wanted was to have it back," she concluded.