But also incredibly good. In Martha Marcy May Marlene, the first of Olsen's marathon run of titles to be released, she plays a young woman who falls into a cult, and whose experiences there - and afterward, when she seeks refuge in the lakeside house of her sister and brother-in-law - can only be described as chilling. It's a stunning performance, deep and indrawn and full of telling silences, as this lost soul struggles with disorientation and dread after a traumatic event.
There's a line Olsen says in the film - "Do you ever have that feeling where you can't tell if something's a memory, or if it's something you dreamed?" - that neatly sums up her character's state of mind.
Olsen, 22, dropped into Philadelphia along with Martha Marcy's writer/director, Sean Durkin, in late August - on the day the city, and the whole Northeast, was rocked by an earthquake. (The interview took place a few hours before the magnitude 5.8 jolt.) Martha Marcy screens Monday in the "American Independents" section of the Philadelphia Film Festival and begins its regular run Friday at the Ritz Five and Rave Motion Pictures at the Ritz Center/NJ.
Durkin, also out of NYU (but a few years ahead of his leading lady), knew he had found his star when Olsen walked in for her audition - one of the last of about 75 actresses to read for the role. He wanted to make a movie about cults without ever saying the word; the scenes at a Catskills commune, where a charismatic hippie type (Winter's Bone's John Hawkes) sings folk songs and messes with his followers' heads (and with the females' bodies), are shot in a low-key, naturalistic style. Durkin needed someone who could look lost in this setting, but not get lost on the screen.
"Lizzie has this ease about her, but also this complexity," he says, seated alongside his star at the Sofitel. "People were concerned that I wanted to go with an unknown. There was this fear that working with an actor who's never had the lead in a film before - never been in a film before, practically - would mean that you'd have to struggle to pull a performance out of her. But I just knew very early on that she knew who this character was, and knew what she was doing."
Olsen says that she actually enjoys the audition process, that it gives her the chance to create a character right from the start.
"I read the script and I was completely obsessed," she adds. "I liked the way Sean told the story - it wasn't linear, it wasn't obvious, it makes you think, it challenges you."
Olsen grew up in Southern California and remains close to her celebrity sisters, and to her older brother and two half-siblings. (Although Olsen resembles another Ashley - Ashley Judd - more than she does either of her saucer-eyed sisters.)
Olsen knew from her childhood days that she wanted to act. In high school, she watched the films of Woody Allen - all of them, obsessively. At NYU, she worked with the Atlantic Theater Company, winning understudy parts in two Broadway shows. She never went on, but she caught the attention of a casting director who remembered her when Durkin's project got going.
It was at the Atlantic where Olsen says she learned how to let go of a character at the end of the day. And with the stuff Martha goes through in Durkin's film, letting go was essential if she was going to keep her sanity. There are tough scenes here.
"Sometimes we'd break for lunch and it was still there - she was still there," Olsen says. "But by dinner, I could leave her behind."
Olsen cites a number of actresses as influences, as inspiration. Working with Fonda on the Bruce Beresford-directed Peace, Love & Misunderstanding was eye-opening. "She's a role model, she'd had this amazing career, and she's so secure in who she is and where she is in her life."
(Durkin says that Klute, the 1971 picture in which Fonda plays a call girl, was one of the films he looked to for visual cues. Roman Polanski's Rosemary's Baby and Robert Altman's Three Women were others.)
And there's Kate Winslet, whose nude scene in Holy Smoke (also, coincidentally, a movie dealing with cults) "gave me the confidence to do my nude scene," Olsen explains. "I understood why it was important, why it was necessary."
Olsen hopes to finish up at NYU next spring - she took 2011 off - but there's already more work lined up. She and Dakota Fanning are set to star in Very Good Girls, about two friends just out of high school who fall for the same New York street artist. She also has made a film with Zac Efron, Liberal Arts, shot this summer in Ohio.
"I'd like to have a long career," she says. "I'd like to do theater, the classics, to work with - well, there are a lot of people I'd love to work with."
Contact movie critic Steven Rea at 215-854-5629 or email@example.com. Read his blog, "On Movies Online," at http://www.philly.com/philly/blogs/onmovies/.