The opening scenes of Fish Tank have us follow Mia (Katie Jarvis), a fierce yet sensitive fifteen-year-old girl, as she roams the sidewalks of urban Essex. She draws blood in a fight with neighborhood girls, tries to free a white horse locked in a empty lot, and comes home to be smacked around by her single mother. She retires to her bedroom, angry and desperate and alone. What keeps Mia likeable throughout is that, despite her toughness, we know she is very much alone in her struggle, and quite vulnerable.

The plot picks up when Mia develops a crush for Conner, her mother’s handsome and charming new boyfriend. Conner, played by Michael Fassbender (Hunger) as both likeable and creepy, is the only person who supports Mia, but it’s unclear what his motivations are. Does he genuinely want Mia to be happy, or does he have a crush on her too? The script, also written by director Andrea Arnold, was filmed chronologically and given to the actors in pieces, each only learning what would happen to their characters a week in advance. This grounds their performances in the moment, and makes the surprises of the second half the film genuinely surprising. Still, the script suffers from occasional lags and several lines of pedestrian dialogue that not even the best performances could fully resurrect.

But it’s Katie Jarvis that carries the film. The majority of the film is a close-up of her face, and it’s her ability to waver between a cold bully and a sensitive, isolated girl full of yearning is what keeps the film interesting. She’s like a less innocent version of Giulietta Masina in Nights of Cabiria, or a less articulate Enid from Ghost World stuck in the world of Thirteen. Mia as character may not be in their league, but Katie Jarvis – if she continues to find directors that allow her to breathe – is capable of real power. We have to wonder though how much of what we see is Mia, and how much Katie. But then, if a performance makes you question if it is a performance at all, you know it’s been effective.

Besides th e creepy-likable Michael Fassbender, the other stand out is Rebecca Griffiths as Tyler, Mia’s little sister with a mouth so foul she makes Hit Girl look like Jan Brady. The only character that didn’t evoke any sympathy is Mia’s boozy mother played by Kierston Wareing. She’s a boozy, self-involv ed single mother who despises her children for reminding her of her age, but Wareing isn’t given the kind of insightful, compassion-building monologue that Mo’Nique was given in Precious, and she remains an unlikable caricature to the end.

It’s somewhat refreshing to see a modern film shot in 1.33:1 full screen. The widescreen format was pioneered to give films an epic feel, but for smaller dramas, full screen fits the mood better. The full screen and hovering hand-held camera combine to give an effect that is somewhat like a home m ovie of a dream. This is not the shaky-cam of docu-dramas; Fish Tank uses its handheld to a llow for a more organ ic flow to the images, as if we were noticing elements of the scene ourselves rather than watching a record of the events. It doesn’t distance the audience; it involves them. The use of natural light adds to the realism of the piece without feeling gritty.

The realism is enhanced with Mia’s grey sweat suit gear, the Ikea furniture, and the prominent mascara-tinged tears Mia sheds by the close of the film. If it weren’t for this grounding in realism, the events of the second half of the film might have felt like cheesy melodrama. Instead, they’re quite frightening.

We mostly hear Mia’s hip hop music, but it’s Bobby Womack’s “California Dreamin’” that stands out, playing three times in the film in three crucial scenes. It adds a haunting, dreamy sadness, and its repetition is like a recurring dream that turns into a nightmare.

Andrea Arnold has a fresh, tart voice that feels distinctly feminine. No man could have directed a film with the feel of Fish Tank. It’s no surprise that she was chosen to helm the upcoming Wuthering Heights, as Arnold is a perfect fit for Brontë’s gothic romanticism.