The actress also weighs in on Princess Dianas real-life smoking and swearing habits.

Ah, the wonders of movie magic.

the massive pearl necklace that Prince Charles (Jack Farthing) has given her for Christmas.

Kristen Stewart as Diana in SPENCER

Neon

But according to the star, the moment almost ended up very different on screen.

So, she suggested they bring it back up to maximize the moment.

And I was like, ‘Yeah but imagine if it was reallyaudible, that crack.’

And so they put it back in."

The problem is, Diana “f—ing hated smoking,” Stewart says.

“There are just certain things you might’t know that happened behind closed doors.

“I just thought it was really important considering we were going to push the envelope so far already.

So any drastic wrongness I was like, ‘You guys, f— no, yo.'”

Speaking of the f-word, did the real princess swear as often as she does inSpencer?

“With the cursing, everyone has a different opinion,” Stewart admits.

Then other people were like, ‘She never cursed a day in her life!’

So I was like, ‘All right, the f—s can stay.'”

Spenceris now playing in theaters.

With reporting by Leah Greenblatt.

Want more movie news?