Sienna Miller Just Revealed All the Steamy Sex Scene Details From Ben Affleck's 'Live by Night'

In the upcoming film Live By Night, Sienna Miller co-stars alongside Ben Affleck. The two have some seriously steamy sex scenes in the flick, and the 35-year-old actress dished on what it was like filming hours of lovemaking.

At the film's premiere, Miller explained that she was unable to control her laughter at times during the filming of the romantic scenes.

Affleck portrays notorious gangster Joe Coughlin in the crime drama while Sienna Miller stars as his Irish love interest, Emma Gould.

In one instance, Ben Affleck, who directed the film, instructed the director of photography to "keep rolling" so they could film the same sex scene "a few times" without being forced to cut, according to E! news.

"I was like, 'OK, obviously Joe Coughlin [Ben's character] is a real performer.' This happened three times, and by the third I [finally said], 'Are you joking?'" Miller said. "And then I was like, 'I don't know what you're trying to tell people, Ben, about your sexual prowess - your abilities."

"It turns out that he was just giving himself options without cutting," she said. "But to me it was the funniest thing. I was like, 'No one can do what you're doing, the marathon love scene.'"

Miller looks forward to seeing some of the outtakes in which she had to remove herself from the set in order to let out her laughter.

"There will be some outtakes from that [scene] where I have to walk out of the room," she said, "because I just have tears running down my face."

Luckily, Sienna and Ben are close pals so the scenes weren't entirely uncomfortable to film.

"Ben and I are like brother and sister, thank God, so there was no awkwardness," Miller said. "There was just a lot of stupid giggling. He's very professional – I am not, but he is."

"In that environment, it was a cool scene," she said. "There was a montage in the script saying we did it everywhere: in the car, in the bar... I was like: 'That's an entire day of just love scenes! OK. How do we do this?"

"Obviously, by the time nine hours of it has gone past, I was shaking with tears running down my face," she said. "I mean, I can't tell you – but you have to laugh. Ben is just professional. It is what it is."

Ben Affleck also dished on what it was like working with Sienna in the sex scenes.

"We were starting over, like all scenes. You start the scene—you get to the end—you go back to the beginning," Affleck said. "Sienna thought that I was trying to make myself out to be some kind of world champion, where it just never ended. I just keep going, going, and going again and again. She started laughing and I was like, 'Laughing isn't really the response that I'm looking for with this.' She was like, 'How long can you go? You're Superman!'"

Live By Night hits theaters on Friday and also stars Chris Cooper, Elle Fanning, Brendan Gleeson, and Zoe Saldana.

Check out the trailer below:

Are you excited to see Sienna Miller and Ben Affleck's Live By Night?

This article originally appeared on www.comicbook.com.

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