In the film the 22-year-old actress plays Martha, an escaped cult member having a difficult time trying to start a new life while living with her sister's family as she's constantaly haunted by nightmares that she'll be either found or worse yet - the victim of the malevolant cult leader's revenge.
At one point in the film, Elizabeth's character is naked for a cult ritual, and the actress had no qualms about stripping off and says the film wouldn't be the same without the scene's inclusion.
"The movie wouldn't have been as disturbing without it," she tells GQ; "Taking away someone's sexuality, making it something you don't even own anymore—that's the scariest thing."
But putting herself out on full display in the film is somewhat ironic, as she wasn't too keen on her famous sisters being followed around and watched everywhere they went.
"The paparazzi were really frightening. I thought, Maybe I'll just skip that part," she says.