Margot Robbie is responsible for one of her new movie's most memorable moments.
The actress reunites with her Once Upon a Time in Hollywood co-star Brad Pitt in the upcoming film Babylon, which premieres Dec. 23. Dubbed by E! News' Francesca Amiker as "what will become an iconic kiss scene," Margot exclusively revealed on the show's Dec. 5 episode (airing tonight at 11:30 p.m.) that her smooch with her co-star was actually improvised.
"That wasn't in the script," she shared, "but I thought, 'When else am I gonna get the chance to kiss Brad Pitt? I'm just gonna go for it.'"
In the film, Margot stars as aspiring actress Nellie, who looks to make her dreams come true in 1920s Hollywood with help from fellow aspiring star Manny Torres (Diego Calva) and veteran actor Jack Conrad (Pitt).
Stating that the kiss scene "was just great," Margot confessed she had to convince director Damien Chazelle in order to make it happen.
"I said, 'Damien, I think Nellie would just go up and kiss Jack,'" the 32-year-old explained. "And Damien was like, 'Well, she could—wait, hold on. You just wanna kiss Brad Pitt.' And I was like, 'Oh, so sue me. This opportunity might never come up again.' And he was like, 'It does work for the character,' and I was like, 'I think so.'"
After a successful take, Margot was happy that she got her one-and-done kiss with Brad. But what started as a fun idea from the Barbie star turned into a moment Damien knew had to be included in the movie.
"He was like, 'No, do it again. That really works,'" Margot joked. "I was like, 'Oh, great.'"
And according to Margot, Brad wasn't the only star she locked lips with during filming.
"I actually kissed Katherine [Waterston], as well," the actress revealed, "but I don't know if that made the cut."
Hear more from Margot and today's entertainment stories on E! News tonight at 11:30 p.m. on E!.
Babylon premieres in theaters Dec. 23.