‘The East,’ Written by Zal Batmanglij and Brit Marling

“The East” is a neat little thriller about ends and means and ethical quandaries. The title refers to a mysterious network of anti-corporate militants whose activities — called “jams” — shade from prankish agitprop toward outright terrorism. The members of the group, who live off the grid in an abandoned house in the wilderness somewhere near the Mason-Dixon line, are determined to hold the poisoners and polluters of the executive class accountable for their actions. Sometimes, as in the case of a pharmaceutical company that has peddled dangerous antibiotics, this means giving the bosses a literal taste of their own medicine.

Written by Zal Batmanglij and Brit Marling and directed by Mr. Batmanglij, “The East” follows Jane, an undercover operative for a private security-consulting firm, played by Ms. Marling, as she progresses from Dumpster diving and freight train hopping to the inner circle where the jams are planned. Jane, known to her new comrades as Sarah, is a former F.B.I. agent who reports back to her boss, a serenely chillyPatricia Clarkson. The parameters of Jane’s mission are not as clear as her almost instantly divided loyalty.

Back home in Washington, Jane has a scruffy, sensitive, bland boyfriend. Out in the woods, she falls under the spell of Benji (Alexander Skarsgard), who is scruffy, sensitive and dangerous. While the East, being a group of anarchists, has no formal leader, Benji is clearly the alpha dog. His main lieutenants are an elfin zealot named Izzy (Ellen Page) and Doc (Toby Kebbell), a troubled former medical student. All of them come from relatively privileged backgrounds and have painful, intimate reasons for taking up the cause.

In general, “The East” is a bit more persuasive on the psychology of its characters than on the politics of their actions. Ms. Marling is a sympathetic presence, in part because her slack-jawed, glassy-eyed passivity is an effective mirror of the audience’s ambivalence. She is initially appalled by Benji and his followers — by their hygiene as much as by their self-righteousness — but gradually finds comfort in the rough simplicity of their thrifty, communal approach to life. The world of work, stability and consumerism feels increasingly sterile and false to her. Mr. Batmanglij and the cinematographer, Roman Vasyanov, register this evolution with subtle visual cues, as the forest and the old dark house become less scary and more enchanted, and everywhere else is drained of color.

Jane’s goodness is as axiomatic as that of a fairy tale princess. While we suspect that she will stray into morally dangerous territory, real evil seems beyond her capacities. In their previous collaboration — the cult film (in both senses) “Sound of My Voice” — Ms. Marling and Mr. Batmanglij played with her aura of guileless blond sweetness to haunting and troubling effect. “The East,” while more conventional in style and structure than that film (or “Another Earth,” which Ms. Marling also helped write and starred in), has some of its spookiness, a sense of ambient vulnerability that extends from the individuals on screen into the very universe they inhabit.

This intimation of large, lurking danger is appropriate to this movie’s vague environmental theme. The damaged, idealistic young people plotting to terrorize the wealthy and comfortable are seen as canaries in the coal mine, their rage a sign that something is terribly wrong. But their animus is also explained in ways that strain credibility and undermine the film’s topicality. Benji, Izzy and Doc are motivated by grief, filial resentment and a desire for revenge. For them the political is personal, which makes it a little less urgent for everybody else.

But it may be asking too much of “The East” — which is, after all, a twisty, breathless genre film — to wish that it would frame the contradictions of contemporary capitalism more rigorously. The movie is aware that they exist, and wishes that they could be resolved more or less happily, which is hard to argue with, though also hard to believe.

“The East” is rated PG-13 (Parents strongly cautioned). Restrained violence, sex and profanity.

The East

Opens on Friday in Manhattan.

Directed by Zal Batmanglij; written by Mr. Batmanglij and Brit Marling; director of photography, Roman Vasyanov; edited by Andrew Weisblum and Bill Pankow; music by Halli Cauthery; production design by Alex DiGerlando; costumes by Jenny Gering; produced by Ridley Scott, Michael Costigan and Jocelyn Hayes-Simpson; released by Fox Searchlight Pictures. Running time: 1 hour 56 minutes.

WITH: Brit Marling (Jane/Sarah), Alexander Skarsgard (Benji), Ellen Page (Izzy), Toby Kebbell (Doc), Shiloh Fernandez (Luca), Julia Ormond (Paige Williams) and Patricia Clarkson (Sharon).