It sounds like a Tarantino-inspired exploitation film - a young white nymphomaniac chained to the radiator in a remote house belonging to an ageing black blues player.

And what a great sell that premise must have been for the studio; not only does it have cool music and Christina Ricci half naked most of the time, it was bound to have conservative film critics dismissing it as exploitation - the sort of underground credibility a marketing budget just can't buy.

That's the surface gloss. Underneath, the most interesting thing about Black Snake Moan is that if you know your feminist theory, you can interpret it as expressing fear and hatred of women. Not the chains or dirt-stained underwear - it's the 'condition' heroine Rae (Ricci) finds herself afflicted with. It starts as discomfort in her head, moves down through her body, causes pain in her stomach and then goes (as Rae describes with a shame-faced murmur) 'lower'. It takes over her like a fugue of psychosis, and she has to grab the next man that falls into her sights and rut with him like a crazed pit bull.

It's not clear how symbolic the device is (much of the movie seems to be), but Rae's sexual urges are depicted as an uncontrollable mania even she can't control, urges that will destroy any decent, God-fearing man close enough. It's a view of female sexuality straight out of the 17th century when PMT was enough to get you burnt at the stake for being in league with Lucifer.

Black Snake Moan will hope to find an audience through such controversial politics, but underneath it's a redemption story we've seen before. After Rae's boyfriend (Timberlake) goes off to the army and her heart breaks, she immediately descends into a panoply of sex, drugs and alcohol which not only dull the pain but get her unceremoniously shagged several times, bashed and left on the side of a dirt road near the houses of small farmer and blues player Lazarus (Jackson).

Lazarus nurses Rae back to health and when she awakens to thank him for her help and take her leave, finds herself chained to his radiator. Jesus put her in his path, Lazarus tells her, and he intends to make her see the light to change her life.

So begins a strange twist on the classic buddy movie with two characters that couldn't be any more different learning to love and save enough other. The central premise - of the chained girl - actually doesn't take up as much running time as you expect, and after it the story veers away and loses strength. Its heart's in the right place but some contradictions, huge stretches of credulity (even within the symbolic framework) and unconvincing narrative elements hold it back from being the great movie it could have been.

Ricci does a great job in the role - not because she's as good in it as you might have heard but because she wants to stretch herself, to say nothing about how hard it just have been to crawl around a house in a tank top, panties and a forty foot metal chain around her waist. She's a little too doe-eyed and overeager to fully convince as the trailer trash town slag Rae. Jackson looks older than he ever has, every bit the old man in the corner of the blues bar singing into his beer about how his wife has left him.

Director Brewer depicts the sweaty, ramshackle American south that spawned the Blues to such effect it almost looks like he's set the film in the 1920s, and the result is a southern barbecue of redemption, biblical references and less of a plot than it needs.

You've probably made your mind up on the strength of how many influential, stuffy critics have passed it off as sexist. Either that, or the chance to see Christina Ricci mostly naked.