The events of Martha Marcy May Marlene are never abundantly clear. A few things are defined: Martha (Elizabeth Olsen) joins a community that turns out to be a cult; she escapes and tries to carry on with her life by living with family; and the cult isn’t really the friendly kind. Everything else is foggy. That’s by design, but there are so many questions left unanswered that, designed or not, it’s a real flaw. The naturalistic cinematography is great, and as the cult leader, John Hawkes (from last year’s indie-darling Winter’s Bone) is electric, but it’s not enough to make the half-assembled story into a great film. Much has been said and written about Olsen, the younger sister of the famous twins, and she’s a surefire Oscar nominee. That’s saying something, because the material is not nearly as good as she is.