Viral

Earlier this year, directors Henry Joost and Ariel Schulman made a splash in UK cinemas with Nerve. Viral muses on some of the same themes - youth culture, interconnectedness and alienation. Despite its more conventional scenario, it's by far the stronger film.

"It's here," screams a newspaper headline, and underneath, "Worm flu arrives in California." No-one is surprised that it is here - we have learned from fragments of broadcast scattered through the opening credits that it has already wreaked havoc in other parts of the world. But even California seems a long way away when you live in a small mountain town where the air is clear and everything closes at 5pm, especially if you're a teenager and you have far more important things to worry about, like your parents' strained relationship, how much make-up you should be wearing, and how you can summon up the courage to talk to the boy you like.

Sofia Black-D'Elia is Emma, younger sister of Stacey (Analeigh Tipton) and new neighbour of Evan (Travis Tope), on whom she has something of a crush. Mom has been away working and it's not clear when she will be coming back. Emma gets the feeling that there's something she's not being told. When her friend Gracie (Linzie Gray) gets ill in class, has a fit and vomits blood, here starts to seem a lot closer. Nevertheless, it comes as a shock when the town is quarantined, the girls' father cut off on the other side of the barrier but phoning with increasingly worrying advice. Stacey takes it as an opportunity to bring home boyfriend CJ (Colson Baker, aka rapper Machine Gun Kelly), and to drag Emma to a party, though getting a lot of young people together in a situation like this may not be the brightest of ideas.

Although aspects of the story are likely to lead to Viral being labelled a zombie movie, it's essentially a character study, observing how the teenagers deal with increasingly straitened circumstances. They're bright and resourceful but still naive, short on critical areas of knowledge and, at times, desperately vulnerable emotionally. As in the similarly atmospheric It Follows and Dear Nachtmahr, this is a film uninterested in using the trappings of youth for mere titillation; instead it immerses the viewer in that emotional landscape, full of once familiar fears. It's an effective means of creating disorientation in older viewers, whilst younger ones will find something that speaks directly to them.

As Emma struggles to take control of her circumstances, she discovers the separateness of adulthood in a world whose new, embodied forms of networking recall the desperate gregariousness of adolescence and hint at an unknowable future. Black-D'Elia brings real assurance to her role and easily carries the film - not that there is a weak performance in it. She has excellent chemistry with Tipton and the sisters' intense bond is convincing from the outset despite the inevitable sparring. Evan is very much relegated to love interest status but it's clear that his support is genuinely valuable to Emma. Much of the humour in the film, meanwhile, comes at the expense of CJ, with the famously quick-witted Baker clearly relishing the chance to play a character who snacks on dry emergency rations as if they were cheesy puffs.

Despite a central story that is inescapably bleak, Viral never drags nor lets the viewer lose sight of its heroine's vitality. It balances thoughtfulness with scenes of frantic action, existential terrors with acute ones. The smallness of the protagonists' world, the hitherto unknown isolation that comes over them when the phone networks go down, combine to show us the familiar epidemic narrative from new perspectives. The world they enter is alien in part because of the disease, in part because it more closely resembles the one the older generation used to take for granted.