It would be a lot easier not to consider Let the Right One In a ‘vampire film’, as attaching this label has a tendency to conjure up in most people’s minds images of Christopher Lee, crucifixes and garlic braids. Tomas Alfredson’s film is in an entirely different sphere from these, a reclamation of the genre both from high camp and from high-kicking high-school girls into a social-realist world where growing-up and not growing-up are equally as painful.

Strip away some of the film’s layers and there is some similarity with fellow Swede Lukas Moodysson’s growing pains drama Fucking Åmål [Show Me Love] (1998), for this is a film primarily concerned with loneliness, trust and loyalty. Oskar is a shy, spindly 12-year-old growing up in a chilly Stockholm suburb, juggled between his separated parents and frequently picked on by the school bullies. In his room he dreams of exacting revenge on his persecutors, manifesting itself in an unhealthy obsession with knives and newspaper stories of grisly murders.

One night he meets Eli, a reclusive young girl who has recently moved into the same apartment complex as him. She is mysterious, with a haunted demeanour which suggests an inner sadness Oskar can well relate to, and the two tentatively begin to strike up an odd friendship, perhaps even a cautious romance. In the meantime, we have already been introduced to Håkan, an older man whom Eli lives with whose main nocturnal habit appears to be stringing people up and draining them of their blood, though at times failing comically.

The viewer has already worked out what Eli’s big secret is, but then perhaps so too has Oskar. In the traditional vampire film, the revelation to the protagonist of the blood-sucker’s feeding habits comes as a moment of intense drama, yet here by contrast it is a gradual understanding and acceptance. Eli constantly hints at suggesting that she is not ‘a girl’, highlighting the outward sexless androgyny of both youngsters; but an imaginative, lonely twelve-year-old boy is more able to accept this as a mere difference rather than a threat. In fact, the central contradiction is that Oskar is seen as ‘good’ for plotting his unnecessarily violent revenge, while Eli is viewed negatively for the killings which she must do to stay alive.

Those expecting an action-packed thrill ride will be disappointed, as the story unfolds at a measured, stately pace, and aside from a few scenes of blood-letting the visual aesthetic is mostly spare and sombre. The architectural setting, a drab Stockholm apartment complex, not too dissimilar from the humdrum Belgium of the Dardennes or even the Poland of Kieslowski’s Dekalog (1989), is far removed from the glamour and mystery of Nosferatu’s Transylvanian castle. Yet there is just a hint of something magically supernatural in the snowy Swedish chill, in particular the beautifully lit night-time exteriors where Oskar and Eli make their first meetings, and in the spellbinding shots of the young vampire’s piercingly-blue eyes.

It is in this juxtaposition of the mundane and the horrific that the film allows us truly to consider its themes of isolation and despair. The familiar vampire traits – fear of sunlight, a bestial thirst for blood, the sadness and inevitable loneliness of never ageing – all carry a hugely greater emotional punch when placed in a deliberately realist setting and placed in parallel with a character with whom some could relate to and most would sympathise with. Not made explicit, but certainly implied, is that Håkan’s relationship with Eli may have once been like that now developing with Oskar, suggesting that even if their friendship blossoms, there is certain to be no conventionally happy ending.

If we are considering Eli’s immortality, then in straight counterpoint to that is Oskar’s very mortality. If childhood is being painted in an entirely unsentimental way here, then so too is adulthood: whilst not demonised, his parents are hardly role models which he could find himself idolising, neither too his teachers, authority figures nor the pathetic adult residents of his apartment block whose petty squabbling and layabout lifestyles the film openly mocks. Caught at the beginning of awkward pubescence, sandwiched between the twin dystopias of childhood and adulthood, it becomes less surprising that he finds solace with a 200-year-old perpetual adolescent after all. He already knows a little about growing up – about ‘going steady’ for instance – but only about as much as he should for his age. But then Eli, whose life for so long has essentially been one long press of the ‘pause’ button at the same age, knows just as little.

Let the Right One In is a profoundly sad film, yet peppered with moments of black humour. Håkan’s bumbling attempts at securing fresh blood for Eli more than once raise the question of what to do if caught red-handed hanging someone upside down with a jerrycan below their bleeding neck. Elsewhere, one woman’s struggle against a band of CGI cats needs to be seen to be believed, and there is one valedictory scene towards the end which somehow brilliantly combines stunning cinematographic beauty and intense off-screen violence, and on top of that will still have everyone in metaphorical stitches.

Great horror films function by attaching themselves to our fears, sometimes rational, sometimes irrational. Let The Right One In, well deserving of being called a truly great horror film, does this by combining the ordinary with the extraordinary, showing them to be mirror images of the same thing, and by placing them within the confines of the everyday then holds the mirror up to the audience to show what we all are capable of doing if the situation demands it. But beyond this, the film is a work of exquisite beauty, of deep yearning and sadness, but also of the comfort and strength that can be found in kinship and love.