Elizabeth Olsen spent more than a few days stripping down on the set of “Martha Marcy May Marlene” in Upstate New York. The independent film, which thrilled audiences at Sundance earlier this year and will finally be released in theaters on Friday.

In the movie, Elizabeth plays a young lady who has just escaped from a cult whose leader played by John Hawkes, who wanted to have physical and mental control over her.

She says she didn’t flinch when her body was “offered up” to a man for sex in one eerie bare scene in the movie while posing in a bra and jacket for GQ.

“The movie wouldn’t have been as disturbing without it,” she explains. “Taking away someone’s sexuality, making it something you don’t even own anymore–that’s the scariest thing.”

While Olsen acknowledges that filming those bare moments was a little strange, she made it very clear that diving into the water was far riskier than taking off her clothes in front of the camera. “The lake was daunting,” she told to MTV News. “Some lake scenes we could only shoot once, because it was physically too cold for a body to be in there very long.”

Olsen, on the other hand, sees her n-k-d moments as just another aspect of the “Martha Marcy” role. She gave a wonderful performance as a lady who escapes a cult and ends up at her sister’s lake cottage, but is constantly plagued by memories of her horrific past. “Everyone’s always put in some sort of weird situation when you’re making a movie,” she said. “I didn’t treat [the nud£ scenes] any differently. The only thing we treated differently was that our first [assistant director] would swap out with our second AD, who was a female, and she’d call the shots.”

But not even the lake scenes are among her most challenging assignments. This honor goes to a stunning, single-take party scene in which Olsen’s character gradually transitions from hesitant partygoer to uncontrollable, voice cord-severing breakdown mode. “What was hard about that is that it was one shot, and it does have a climax to it. It was also our first experience with lots of extras, and these aren’t people who are actors. They’re just people in town who wanted to be in a movie, so they love talking to you in between takes. That was distracting. Personally, that was my most difficult scene to film.”

Despite the demanding nature of the part, Olsen claimed that the character didn’t stick with her once the summer’s filming was through.

“It wasn’t very difficult to leave behind,” she explained. “I always keep myself very separate from a character, not trying to think that I’m the character or all those things, because especially in this movie, that’d be very bizarre. What I did leave behind, which I really missed and what was really sad, is all of these people became really, really close friends of mine. Thank God they all live in Brooklyn! So we’ve been able to hang out all the time. We did have a very special experience making the movie.”

Also scary? Growing up with kid stars Mary-Kate and Ashley, who were besieged by fans and photographers wherever the family went.

“The paparazzi were really frightening,” Elizabeth tells GQ. “I thought, Maybe I’ll just skip that part.”

On October 21, Martha Marcy May Marlene will have a limited release.