When they move into a new home, the Lambert family become increasingly suspicious that they are being haunted by Casper’s worst nightmare. When packing up and moving again doesn’t help and their son falls into a mysterious coma, Josh (Patrick Wilson) and Renai (Rose Byrne) must recruit the services of an old acquaintance and rely upon the unorthodox methods of an ageing medium (Lin Shaye). As the supernatural threat grows more potent, and the shit really starts to hit the metronome, a family secret may hold the only key to their son’s condition in what has suddenly become a desperate race against time.

As somewhat of a connoisseur when it comes to cinematic horror, I like to think I’m braver than I actually am. In fact, the reason that I love the genre so much is that I am one of the most susceptible people I know to Hollywood’s staid horror conventions and recycled scare tactics. Therefore when I say something is scary, I am prone to a rather large margin of error; when I say that something is not, however, you can trust my judgement emphatically.

With that in mind, then, let me first say that Insidious is one of the downright stupidest horror movies I’ve ever seen, with each turn of the plot eliciting a new groan in the knowledge that things are about to get a whole lot sillier. If I was sustaining a cringe throughout, however, it would have been near impossible to tell; safely hidden, as my head was, behind the palm of my quivering, sweat-stained hand. Insidious‘ biggest achievement, and perhaps the only one that counts, is that it doesn’t shy away from less accepted territory and unintentional humour, but embraces them; somehow managing retain a considerable sense of dread regardless.

Marketed as it is as from the creators of Saw and Paranormal Activity, it is easy to see why some people might be disappointed by Insidious‘ apparently blasé attitude to cheese. If I was to compare Insidious to any recent addition to the horror genre it would probably be Sam Raimi’s Drag Me To Hell, with an ending that could be right out of Joe Dante’s The Hole in 3D. You see, rather than using its malevolent spirits with a near tedious restraint, Insidious isn’t going to waste hours of make-up and thousands of dollars of special effects on a few throwaway glimpses, it’s going to flaunt its assets at ever available opportunity.

What this should do – and perhaps to a braver soul, does – is render the audience desensitized, accustomed as they have come to the film’s primary antagonist (a demonic threat that could easily be reduced to Darth Maul running around in a dark room). Director James Wan is so shameless in his desire to scare your popcorn out of its box, however, that his confidence somehow translates into genuine, excruciating terror.

As in Drag Me To Hell, Insidious boasts acting that is best described as heightened, particularly when the hauntees turn, inevitably, to the resident psychic. Proceeded by two bumbling ghostbusters, the eventual reveal of our Betty White-a-like continues the film’s attempts at self-sabotaging its own tension, the requirement that she wear a gas mask to perform the climactic séance upping the ridiculous quotient to giddying levels. We really are talking Resident Evil: Apocalypse levels of subtlety as the ghouls come knocking, and yet it all somehow works, completely despite all of the hackneyed talk of astral projection, demonic travellers and The Man With The Red Face – not to mention the final confrontation with Mr. Maul himself.

Whatever Insidious is supposed to be, then: a deadly serious assault on your sleep cycle; a homage to such films as Ringu (our protagonist isn’t particularly photogenic), The Shining (those twin girls really do get around, don’t they?), and Poltergeist (young children should just be outlawed); or simply an unused plot from Buffy or Ghost Whisperer, Insidious is as bonkers – and absolutely terrifying – a film as you are ever likely to see.