Apt Pupil is arguably the best thing Stephen King has ever written. Which is not saying so much, admittedly, but just stop and think for a moment. How much of what you know as King has anything to do with his actual words? You think of The Shining and you think of Kubrick’s movie. You think of Salem’s Lot and it’s that epic TV adaptation and the little boy tap-tapping at your window. Carrie? De Palma. Misery? Kathy Bates in a bad mood. King’s books have become little more than Hollywood blueprints. And made him very rich into the bargain.

But Apt Pupil is slightly different. It was published in 1982 as part of the novella collection, Different Seasons, the book that also gave us the grossly overrated Shawshank Redemption. And contains possibly the nastiest episodes King’s brain has ever committed to paper. For its monsters are not ghosts and ghouls and vampires but Nazis. One real Nazi, Dussander, who conducted experiments in the camps. And one apprentice, Todd Bowden, an all-American straight-A student who, having identified the old man in his neighbourhood as a war criminal, indulges his nascent fascination for Reich chic by blackmailing him into recalling ever more lurid details.

A previous attempt at the film, in the late eighties, collapsed after ten weeks. There it was Nicol Willamson as the old man and, in what strikes one as perfect casting, the blond, blue-eyed former über-moppet Ricky Schroder as his murderous acolyte. Well, that we will never see, but it did open up the way for Bryan Singer, fresh off the back of the acclaimed and awarded The Usual Suspects, to make his own valiant stab. The results are surprising.

Brandon Boyce’s screenplay turns the first two-thirds or so over to a virtual two-hander, only opening things out towards the end, after Bowden has walked away and when a heart attack puts the old man in hospital. The bulk of the film is, therefore, almost theatrical, and -- with some validity -- seeks to refocus the story, pushing the burden of the relationship back onto Dussander. Boyce has all but removed (as the film’s relatively benign certificate evinces) King’s excess. The vivid, disturbing sexual episodes are absent here, and the potentially exploitative elements in the original are only really glimpsed in a crude sequence that has Bowden’s shower companions turning into shaven, emaciated victims. Sensibly, the film rejects the obvious and we see no flashbacks to the camps.

As Bowden, teen pin-up Brad Renfro is fine, providing just the right degree of empty-eyed middle-class, Trenchcoat Mafia-ness to offset Ian McKellen’s furious playing of the unrepentant Nazi. But given that the screenplay spends so much time pitching these two off against one another, the impressive supporting cast is rather sidelined. Thus Joe Morton’s cop and Bruce Davidson as the father get very little to do, and the excellent Elias Koteas, as a neighbourhood bum, is literally wasted. Singer, though, again proves himself an interesting if rather traditional film-maker, and the film is both edited and intriguingly scored, like Suspects, by the multi-talented John Ottman.

In the end Boyce and Singer have all but rewired Apt Pupil. This is no longer a tale of innocence corrupted so much as evil calcified. You will not find the original’s finale anywhere near these frames. Instead, the film goes out on a whisper instead a bang and is all the better for it, turning the often lurid original into something rather more subtle. The results are creepy and queasy more than gross-out, responsible rather than exploitative. Streets ahead of the rotten Misery or tedious Dolores Claiborne (among the more favoured adaptations), it will have to fight hard to be recognised as among the best of the cinematic Kings swamping an already overcrowded market.