The US actress talks about her complex first lead role in Martha Marcy May Marlene.

The younger sister of the Olsen twins stepped into the limelight in 2011 with an entrancing lead debut in Sean Durkin’s Sundance hit Martha Marcy May Marlene.

The California-born graduate of NYU Tisch School of the Arts says her nascent career “just kind of happened naturally”. Her agent alerted her to the drama about a cult refugee. “Sean had an open call for every person who was age-appropriate, so I went and he called me back a few weeks later.”

The film shot in summer 2010.

“He writes more than he intends to film and he films more than he intends to have in the movie,” Olsen says, “so a lot of the character’s background is in the script. I had a gut connection to her. I was interested in her sense of paranoia; it was less about a cult than surviving trauma and how people react to that.

“I thought I understood her. I come from a place where I have always had a big community of family and friends, but if someone didn’t they would have this void of not really having a plan in life, so a community like that with John Hawkes where they provide unconditional love offers a place where you feel you are actually needed.”

When Martha flees the cult and arrives at her sister’s lakeside getaway, Durkin’s hairpin narrative enters a subtly unsettling stretch. “The family life Sean wanted to convey is [one where they don’t] talk about things that need to be talked about and talk about things that needn’t be talked about.” The finale shows us there is no escape. “She still has this sense of not knowing what will happen.”

Olsen’s other Sundance 2011 entry, Silent House, opens soon in the US and she returns to Park City in January with Liberal Arts and the thriller Red Lights, before shooting commences in April on Therese Raquin opposite Glenn Close.