Our entry into this world is Sarah Moss (Brit Marling), a young woman with some government experience (FBI, perhaps) who has now moved to the private sector, hired by Hiller Brood's top executive, Sharon (Patricia Clarkson), to infiltrate a collective called The East. By necessity, The East operates under strict secrecy, so Sarah's process for going undercover is painstakingly elaborate. Fans of spy movies will find this aspect, along with Sarah's continued efforts to remain undetected, enjoyably suspenseful.
The East is a cult-like entity of about 10 people, led by Benji (Alexander Skarsgard), a charismatic and intense young man who reveals little about his pre-activist life. With a dilapidated house in the woods as home base, the group has someone with medical training (Toby Kebbell), as well a computer hacker (Danielle Macdonald) and people with other useful skills, and they're not malicious. "Anarchist" is a strong term, though it's the one their target corporations use. Their "jams," as they call them, run along the lines of covering a CEO's house in crude oil, the way his company did to the Gulf of Mexico, or forcing someone to take a dip in the lake that he swears his factory isn't contaminating.
This is the second feature film from director Zal Batmanglij -- and curiously, his first, "Sound of My Voice," which he also co-wrote with Brit Marling, was also about someone infiltrating a secretive, cultish group whose members' convictions run deep. Sound of My Voice was about religion and faith; The East is more broadly about our moral stances: how we arrive at them, how they can change over time, and whether we view those changes as positive or negative. We sympathize mostly with the environmentalists at first and assume the story is about Sarah being converted to their side, but then we come to see other perspectives as well. Marling conveys her character's conflicted emotions well, giving us a view into both sides of the battle while keeping us enthralled by a thorny, tense story.