The Dirties

Two movie-obsessed high-school students Owen and Matt (Owen Williams and Matt Johnson, who also writes and directs) are making a short movie about bullying for their film class. After they show it, to widespread derision from their classmates, the bullying gets worse (by boys they call the "dirties") and so the two teenagers decide to make a new version, incorporating secretly filmed footage of them being harassed and assaulted.

As Owen and Matt develop a narrative for the foul-mouthed, Tarantino-esque movie, it becomes increasingly about enacting revenge on the dirties. Matt is the driver of events. He fantasises about enacting a Columbine-style shooting at the school - but “killing only the bad guys” - draws up a list of who he wants to kill, and obtains a gun from his weapons-mad cousin.

Owen, meanwhile, thinks it's all a joke and is more interested in getting off with pretty classmate Chrissy (Krista Madison). He has an achingly embarrassing plan of his own - to be playing the guitar as she walks past him in the corridor so she'll think he's a sensitive guy. Only thing is, he has to learn to play the guitar first.

It becomes a film within a film within a film. Is that meta enough for you?

As we see Matt and Owen create their home movie, throwing in a plethora of film references from Trainspotting and The Usual Suspects to Reservoir Dogs and The Royal Tenenbaums, the line between reality and fake begins to blur: “I don't know what's real with you and what's not real,” Owen cries in frustration at one point – and we know it's going to end badly for somebody.

The film is presented mostly as found footage and, as we also watch events being recorded by an unidentified camera operator, The Dirties becomes a film within a film within a film. Is that meta enough for you? Whoever this person is recording events, he or she never interacts with Matt and Owen, even when Matt's plan comes to violent fruition. We may wonder why the person behind the camera doesn't intervene at several points – when Matt gets the gun, for example – but by then we too are complicit as witnesses to the unfolding story.

Filmed at a real school with its students and teachers providing a convincing backdrop, The Dirties has two nicely judged, naturalistic performances by Johnson and Williams at its centre. Even if the former looks a little too old to be a high-school student he makes an accomplished debut as director. There are some delicious, darkly comic moments – such as when Matt tries on several different outfits, deciding what to wear for the shooting – but this is a film with a serious purpose, to try to understand why some people act out dangerous fantasies. It may come to no definite conclusions but it makes us ponder the question.