Sean Durkin's debut feature gets under your skin and burrows there; you can't quite shake it off. Its central figure is a young woman named Martha (Elizabeth Olsen), who has the ever-shifting, not-quite-formed quality of someone still in her teens. In a narrative that constantly moves us between present and past, we learn in the film's early stages that Martha has fled a rural cult, led by a charismatic, vaguely Charles Manson-ish figure named Patrick (John Hawkes). Calling her sister Lucy (Sarah Paulson) from a pay phone, she clutches the receiver like it's a lifeline; barely knowing where she is or why she's running, only that she has to run.

Though sparing with the details, Durkin eventually reveals to us that Martha has few options; her mother has died and Lucy is her only family. You can see how this vague woman-child would drift into something that seemed warm and inviting, as the farmhouse cult initially did — until Patrick raped her, as he does all the young women who join their "family," and showed her how to use a gun, casually suggesting she shoot another cult member.

"You're my favorite," he murmurs to Martha, and she's sufficiently immersed in the cult's water as to believe him, if only for a moment.

"Martha Marcy May Marlene" (the title combines the various names the central character is given) mostly takes place at the elegant Connecticut lake house of Lucy and her husband, Ted (Hugh Dancy), whose welcome to Martha is reluctant and confused. They don't know what to make of this little sister, who won't say where she's been (other than a vague story about a boyfriend) and who seems to have lost all appropriateness, trying to crawl into bed with the two of them. We live in Martha's head as she remembers details of her past; blurry shots, coming into focus, show us how she's trying to find her way.

Through music, eerie light, subtle yet effective cinematography (watch how the camera ever-so-slightly pulls in closer on Patrick, as he smiles) and a well-cast group of remarkable actors, Durkin shows us a nightmare and its aftermath blurring together. This young woman can run but, right up to the film's enigmatic final shot, she can't find anywhere to hide.

Moira Macdonald: 206-464-2725 or mmacdonald@seattletimes.com