Movie review: 'The Sound of My Voice'

This is the question at the heart of “Sound of My Voice,” one that you'll be asking yourself until the very end and even afterward.

Brit Marling follows up on the promise of last summer's “Another Earth,” another sci-fi thriller that makes the most of its meager budget with intimate settings, well-drawn characters and steadily mounting mystery. Marling co-wrote, coproduced and stars in both, and once again she leaves a strikingly naturalistic impression.

“Sound of My Voice,” which Marling wrote with first-time director and fellow Georgetown University alum Zal Batmanglij, is the stronger film of the two, though, with its gripping tension and relatable realism. “Another Earth” benefitted from an intriguingly fantastic premise, but you could easily imagine what goes down in “Sound of My Voice” — you could see how people allow themselves to get sucked into this sort of murky world.

Before we get to Marling's character, though, we meet mousy Peter (Christopher Denham) and reformed party girl Lorna (Nicole Vicius), dating documentary filmmakers who have infiltrated a San Fernando Valley cult in hopes of exposing its leader, Maggie, as a fraud. The sequence in which they're blindfolded, bound and stuffed into a van, then forced to strip, shower and dress in simple white clothes upon arrival is one that's repeated with each visit, with increasing speed, in a beautifully fluid bit of editing.