Let's start with a confession: I've never much cared for The Shining. Sure, I can admire it as a magnificently mounted work of art, but I don't really enjoy it very much. Stanley Kubrick's glacial style, so effective for the sterile, emotionless, repressed and nihilistic worlds portrayed in films from 2001 to Barry Lyndon simply doesn't work in the horror genre (and despite the claims thatb this documentary studies, a horror film is what this is), and Jack Nicholson's scenery-chewing effectively kills any chance the film had of being scary. While many films have been rightly critically reassessed over the years, I think in this case, the original reviews were probably more accurate.

But in recent years, The Shining has been elevated by critics into a self-fulfilling role as The Greatest Horror Film Ever Made. This title has, of course, been bestowed on the film mostly by film critics and commentators who don't like or watch horror films – people who would routinely consider the genre, be it Hammer Horror or Saw or any points between, to be somehow beneath them and the stuff of mentally deficient knuckle draggers. No surprise then that not only would they immediately assume that a horror movie made by the increasingly sainted Kubrick has to be the best of the genre but that they would mistake the horror tropes that the film contains - and it contains plenty - to be original inventions (and so allow them to make ludicrous claims like 'every horror film made since 1980 is heavily influenced by The Shining').

But because Kubrick is such an enigma – taking years to shoot movies, demanding multiple retakes, a stickler for details and, more importantly, not giving interviews or audio commentaries to explain his work – it's inevitable that there will be those who are determined to find greater meaning in his films than appears on the surface. This is, after all, the man who made 2001, as symbol-heavy and multi-layered film as you could hope to see. And because he is 'known' to be such a perfectionist, then clearly there can be no accidental moments, no mistakes, no random choices in a film like The Shining? Clearly, this 'horror film' must actually be about something else . It's an appealing thought, especially if you are the only person to spot these secret messages, making you more aware than the brainwashed masses. Why, it's like you and Stan are sharing a private joke! You could, of course, find similar hidden meanings in more or less any film if you were so inclined and obsessed...

Room 237 explores assorted conspiracy/hidden message theories surrounding The Shining, using the words and voices of five theorists, and clips from the film itself alongside Kubrick's other films and movies as varied as Demons and The Eagle Has Landed. Split into nine sections, the film allows the various commentators – unseen so we can't leap to knee jerk reactions about their theories based on how normal or crazy they look – to expand on their theories of what the film is really about.

This is, of course, an authored documentary. These interviews are certainly edited (apparently, only 10% of the recorded interviews made the final cut), but there seems little evidence that any comments are used out of context or edited to make people seem silly – they manage that quite well by themselves. There are various competing theories about the film – which in itself should be enough to tell you they are all wrong – with the most deluded being that the whole movie is about how Kubrick faked footage of the Moon landings (the explanation that 'Room No. 237 is obviously an anagram of Moon' is jaw-dropping'). These are people who developed a theory about the film and then went on to obsess over every detail, making every little insignificant moment fit to their frankly ludicrous ideas. This often involves talking up moments that are simply not there – you can see Kubrick's face in clouds during the opening titles (no you can't), there's a picture of a Minotaur on the wall (no there isn't), a minor character 'representing' American Indians gives a submissive sigh (no he doesn't). That some of the people making these claims – that the film is about the oppression of American natives, the Holocaust, the moon landings, the number 42 (these people would have a field day with The Hitch Hiker's Guide to the Galaxy!) etc – are broadcast journalists or 'intellectuals' doesn't make the theories any less a case of swivel-eyed lunacy. Smart people are just as capable of obsessive craziness as anyone else. More so perhaps, since they often consider themselves superior to the proles and thus able to spot things that the rest of us miss.

Post-modern film criticism also raises its ugly head here, with the claim that even if Kubrick didn't place all these 'clues' in his film deliberately, that doesn't invalidate them because of course a film can have a meaning that the filmmaker was unaware of. Post-modern film criticism is, of course, mostly a load of cock that appeals to self-proclaimed academics who like to think that they are so smart that they know more about the meaning of a movie than the people who actually made it, and it's perhaps unsurprising that the biggest critics of Room 237 have emerged from this circle (jerk) of writers. It's never fun having your pomposity pricked.

None of this is to say that there are not layers to The Shining, or that the film is entirely one-dimensional. Certainly, the most interesting parts of Room 237 are the examinations of continuity errors and the nonsensical layout of the Overlook Hotel set. While these are discussed at length, no one seems to be able to explain the significance of them in conspiracy theory terms. Might I suggest that someof them could be simple continuity errors - something Kubrick fans might consider an impossibility given his obsessive nature, but surely a strong likelihood in a film shoot this long. When Danny finds himself suddenly facing the wrong way on the carpet pattern when meeting the ghostly twins, it's stated that this must be deliberate because of the effort in changing the camera set up, but no one seems to take into account that the two shots may have taken place days or weeks apart.

Alternatively, Kubrick might – and in certain instances almost certainly was – engaging in a long-established, if underused horror movie trick of unsettling the audience by making subtle changes or adding subliminal images that they wouldn't consciously notice but that would register in their subconscious, creating an unsettled feel that things are not quite right. The Black Cat was doing likewise in 1934. Certainly, from what we know about the set design, it seems the hotel was deliberately designed to be an architectural impossibility, partly to facilitate the story and partly to unsettle the audience and establish the ghostly, not-normal world of the film. This is hardly a secret code, it's just established horror film production technique, like the jump-scare, the false scare and the ghostly figure in the background.Unsurprising then that these tricks seem so revolutionary to people unfamiliar with the genre.

Room 237 will probably drive to to distraction, make you laugh out loud, shake your head in despair and – with its myriad of clips – provide you with a 'name that film' party game for the future. Director Rodney Ascher does a fine job of balancing the competing interpretations and marrying ideas to visuals, and allows those ideas space to be expanded on without overtly mocking anyone – hell, he hardly needs to.

It'd be nice to think that seeing this would make some of the people involved come up for air and perhaps get a grip on reality, though I imagine that's very unlikely. I'm all for serious film analysis – but sometimes, we need to dismiss the dissertations of alleged academics and remember that, in the words of the Last House on the Left poster, 'it's only a movie... only a movie... only a movie...'.

DAVID FLINT

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