Are you sitting comfortably? At least half of you won't be by the time the end credits roll on this compelling and stylishly psychological thriller that almost makes you feel sorry for a paedophile. Almost.

The guilty offender is 32-year-old photographer Jeff (Wilson, Phantom Of The Opera) who 'grooms' junior high-schooler Hayley (Page) before meeting her for morning coffee.

Impressed and turned-on, Jeff throws caution to the wind when she insists on seeing his pad. His ego gets a further boost when Hayley sings the praises of his portfolio while mixing him a cocktail. Then everything goes blurry...

He regains consciousness to find that Hayley has tied him to a chair and ransacked his home. But she can't find what she's looking for and demands to be told what he knows of a local schoolgirl who recently went missing.

Jeff's annoyance turns to panic when Hayley anaesthetises his lower abdomen with ice, produces a surgical handbook, a camcorder, a pair of scissors and a scalpel.

Cross your legs and hope to die, Jeff, because you're not going to be the pervert you used to be.

This is the most riveting two-hander to come along in ages, combining the horror of Misery with the moral ambiguity of David Mamet's Oleanna.

While director Slade shoots in a uniquely arresting style (the 'Digital Colorist' gets his own credit), writer Brian Nelson provides a few jabs of welcome humour to make the tension more bearable.

When Hayley threatens to expose Jeff for what he is, he wails that what she's doing will end his career and ruin his life. "Didn't Roman Polanski just win an Oscar?" she asks.

Interestingly, Jeff pleads for mercy but never repents for his actions at any stage of his ordeal. Though aware that his behaviour is shameful and unacceptable, he doesn't see himself as a wrong-doer because he "never hurt anyone".

But Hayley is a different matter. Is she to be applauded as a crusader for moral justice or avoided as a deranged sadist? Viewers are left to decide who the bad guy is.

If there is a flaw, it's that Hayley is far too smart to be entirely convincing; 14-year-olds just aren't this sharp. But in Ellen Page we have an early contender for the best actress of 2006.

Elliott Noble