Scott Wise’s review published on Letterboxd :
There's a genre of thriller somewhere between the horror and crime genres that I really miss in the film world. I remember, growing up through the 80s and 90s, how many gripping thrillers captured my attention by placing compelling tension within an everyday world. Where believability survived in compelling characters and both plot twists and revelations hit fast and hard. They were rarely good, mind you, but they seemed much more common. Movies like Cape Fear, The Silence of the Lambs, and The Game stood out to me as stories and ideas that could actually exist in the real world, making them all the more engaging and ultimately satisfying.
True thrillers perhaps need to now be classified as a sub-genre of thrillers on the whole. These now come more rarely, where thrillers instead lean much more heavily on crime (Collateral, The Departed), action/war (Taken, Zero Dark Thirty) or fantastical elements (Inception, Black Swan, Source Code) that - although thoroughly enjoyable and great on their own merits - are not like what I'd call a true thriller. They aren't grounded in an approachable real-world context, one which I can easily project my own experiences into.
With the exception of blink-and-you'll-miss-it short-run studio seconds (Arbitrage and The Ghost Writer come to mind), we rarely get a movie as good as The Girl With The Dragon Tattoo that clearly falls into this genre without relying too heavily on crime, action or fantasy to build a thrilling narrative.
The East is that kind of thriller, and it's a diamond in the rough.
The film follows Brit Marling (Sarah), an operative for a private corporate investigation firm tasked with going undercover to discover and infiltrate a Blac Bloc-like environmental activism/terrorism group attacking their clientele.
The film does a great job of demonstrating Sarah's psychological limbo between the activists she has come to know and understand and the life she has spent her career building. It becomes precarious, and Marling is exceptional in conveying the unsettling truth of her situation - wrestling with her own beliefs and coming to grips with the ethics she used to see with clarity. Her journey to discover whether her feelings are a sort of Stockholm Syndrome or a deeper change in perspective are conveyed beautifully, and we as an audience are right there with her, battling with the same questions.
Of the other characters that round out the cast, Alexander Skarsgård and Patricia Clarkson are clearly the most considered, each demonstrating polar opposite traits and intentions. Although a clear foil, Clarkson displays a resolved detachment and somehow manages to turn a flat two-dimensional character into something more sinister. Skarsgård's Benji improves drastically as we learn more about his troubled past and his own motivations for involvement in the activist movement. While Ellen Page gets high billing, I found her character one of the weakest. Despite wearing her political/familial motivations on her sleeve, her personal relationship motivations are not explained and she seems to have been inserted as the unapologetic radical archetype of the group without being given much meat to chew on. Toby Kebbell's Doc has a much more interesting backstory and it was easy to grow sympathetic to his character and the inter-personal relationships he has with the group.
The plot has a few hiccups in developing itself; it seems far too easy for Sarah to discover and be brought into the movement itself, and more attention could have been paid to setting up The East as a legitimate concern rather than a group of radical pranksters. Once it's up and running, however, I found it more than engaging through the bulk of the film. There are several tense moments and some interesting ideas presented. But the film's arc also suffers greatly from a third act twist that is duller than it should have been, where tension is diffused too quickly and without needed impact. There's little follow-through here, and an epilogue is presented over the end credits that leaves a sense of ill-considered closure where a much more thought-provoking ending was an obvious option that I think would have been a better choice.
Overall, I would still recommend the film and it does present some interesting ethical ideas in new ways. It's also the type of thriller I'd like to see more of, in case you didn't catch that up front.