Kings Of Leon, Brixton Academy, London

In light of the Kings of Leon's self-confessed devotion to liquor, it comes as little surprise to find three-quarters of their audience in an advanced state of inebriation before the gig has got under way. The floor is awash with beer and when the band finally arrive on stage they are welcomed with a volley of plastic pint glasses and frenzied exclamations of joy.

The hirsute four-piece from the wilds of Tennessee - brothers Jared, Nathan and Caleb Followill and their cousin Matthew - are salty purveyors of whiskey-soaked rock and southern blues reworked for the post-White Stripes generation. Not only do they rock like monkeys, but their story is the stuff of which lucrative record contracts are made. The sons of an alcoholic (and now defrocked) travelling minister, the Followills' childhoods were spent roaming around the American south, living off the charity of friends and converts. Earlier this year they appeared on our shores apparently fully-formed and with a debut album packed with seedy tales of prostitutes, transvestites and bar-room brawls. Now they've sold 300,000 records in the UK alone and are playing venues that befit a band at least twice their age and experience.

It's doubtless a result of the Followill's rootless upbringing that they have adjusted well to their new-found success. While the music is as lowdown and dirty as ever, it's clear that work has gone into their wardrobe. Guitarist Matthew looks like a cross between Sonny Crockett and an Irish water spaniel with his peaches-and-cream jacket and billowing hair, while Caleb, the bearded frontman with a voice somewhere between Creedence Clearwater Revival's John Fogerty and AC/DC's Bon Scott, seems to have fashioned his hair from a medieval helmet.

That tonight's largely male crowd spans several decades suggests the Kings are more than a passing fad, though the number of Robin Hood goatees in evidence bodes badly for fashion's immediate future. The show opens with the rollicking "Red Morning Light", but the sound system lets them down. The vocals are muddy, the guitars inaudible and the music's propulsive force peters out somewhere near the edge of the stage.

It's only when the guitars are finally turned up (has the sound person only just turned up for work, you wonder) that you realise what fine musicians the Followills are, conveying a mood of loose-limbed vigour while maintaining a pleasing tightness and definition. Caleb is an extraordinary front man, screeching and wailing like a cat in labour one minute and whispering sinisterly the next. He can be charming too; when he shyly wishes us all a merry Christmas, it's all you can do not to run on stage and give him a hug.

With each track, the Kings of Leon seem to grow in confidence and stature (admittedly, it does help that nearly every one of their songs is memorable). By the time they reach the smoky "California Waiting" and the incendiary "Holy Roller Novocaine", the room seems to have been magically transformed into a seedy New Orleans bar (complete with sticky floor) and the Followills are ungodly preachers sermonising on how best to sell our souls. Amen to that.

Touring to 22 December