Rachel McAdams’ sex scene in “Disobedience” was something the actress has never experienced before.

The 39-year-old star opened up to Entertainment Weekly about her once-in-a-lifetime simulated sex scene with co-star Rachel Weisz.

“Often, you’re trying to decide if it’s gratuitous or not,” McAdams said of filming sex scenes, “but this scene felt so integral to the plot and moving the story forward.”

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“The characters need this release to open up. There was energy to that scene that I haven’t experienced in any other sex scenes in my career.”

McAdams felt a sense of “camaraderie” to the woman-on-woman scene: “We both felt safe and free… All those things that you love about being a woman, you get to be [in the scene], so I understand the attraction and appeal to that in a sexual context.”

And the actresses don’t perceive “Disobedience” to be using sex to drive sales. “[It] is a massively important and beautiful scene,” Weisz noted. She revealed director Sebastian Lelio “storyboarded it precisely a couple weeks before we shot it.”

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“He made it clear everything he wanted: the wetness, me spitting in Rachel’s mouth, and [a focus on] Esti’s orgasm — my character [originally] had an orgasm, too, but I had to agree as a producer, even though it was a very good orgasm, it wasn’t as good for the story as Esti’s,” Weisz said of Lelio’s direction.

“In that moment, Esti’s orgasm is both a sexual release and a metaphorical release to freedom, it’s like she’s free to find out who she really is,” she explained.

“Disobedience” makes its way to theatres April 27.

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