Seen live, The Prodigy are certainly provocative, says Ryan Gilbey, and it's not just because of Maxim's frocks.

Jack rabbit rhythms. Vibrant, pulsing physicality. A sense of daring that makes you catch your breath. Yes, the break dancers who supported The Prodigy in Manchester last weekend were really something.

It was an unusual decision to include these human spinning tops in the show, given that break dancing has now been relegated to the status of the Hula-Hoop, but it conjured a retro flavour that is more pertinent to The Prodigy than might at first be apparent.

The band grew up in the Eighties, and the influences which they have collected from that garish decade manifest themselves in their stage-show: the police sirens on loan from Public Enemy, the mix-'n'-match fashions cobbled together from the Pop Will Eat Itself dressing-up box, and a sense of rambunctious self-aggrandisement that has a whiff of Guns n' Roses about it. There's a lot that's wrong with The Prodigy but you can't fault their showmanship: they've created the most spectacular pantomime in town.

It's disappointing that most bands only feel obliged to put some thought into such matters as staging and costumes if they're playing Wembley Stadium, and even then it usually amounts to nothing more than the odd hydraulic bridge or a couple of inflatable lap-dancers.

Pop music is an inherently theatrical form, yet many modern popsters seem too timid to risk even a scissor jump, as if embracing that theatricality would disqualify them from being serious musicians. It's unlikely that there are any more Ziggy Stardusts in our midst, if only because most bands recoil from the use of lipstick and eye shadow, let alone the thought of creating extra-terrestrial alter-egos. In this barren, conservative landscape, The Spice Girls' decision to stomp around in chunky pumps the size of armchairs is positively revolutionary.

It's heartening that The Prodigy choose to embrace the idea of live performance as an art form in its own right, rather than just an adjunct to their latest album. It's crucial too that they tap into the gang mentality that has been an integral part of pop music since the earliest rumblings of rock 'n' roll. Liam Howlett is the techno boffin who spends the show scouring around between keyboards while Leeroy is the band's fairly hopeless dancer, presumably accommodated to assure those insecure audience members that, however badly they dance, there's always someone worse.

The Prodigy's twin ringleaders give the band its pulse. Maxim is a commanding colossus of a man who unfortunately suffers from a little-known condition which makes it impossible for him to start any sentence without the words "all the people in the house..." He stalks around the stage pulling irritable faces that are intended to denote barely suppressed pre-millennial tension, but actually suggest the anxiety of a man who's just remembered that he's left the stove on. Still, he's a big chap who wears a skirt and I know better than to question the behaviour of someone like that.

While Maxim's hectoring act can get a bit tiresome, watching Keith Flint is like tuning in to the most grotesque and breathtaking nature documentary that David Attenborough never made. In keeping with the band's theatrical nature, both Maxim and Flint spend the entire show in character. No chummy between-song banter for these gargoyles. They spend every second on stage twitching and grimacing and bearding their fans, and you've got to admit that it makes a change. Flint looks like the sort of creature you usually see bursting from people's stomachs in horror films. He lets his pierced tongue flop out of his mouth like a carpet unfurling, the saliva yo-yoing from his chin: he's everything your mother warns you about. Imagine what he's like at meal times.

The blistering energy of the show makes it all the more regrettable that the band don't have the musical innovation to back up their visual daring. The Fat of the Land is one of those albums that was acclaimed months before anyone had heard it - the sheer weight of expectation somehow got translated into critical approbation and nobody seemed to notice. Actually, it's one of the most unfocused albums of the year, though the fact that its tedium is punctuated by "Firestarter" and "Breathe", two contenders for single of the decade, has distracted many listeners from noticing that the remaining eight songs are filler tracks. Played live, the force of the crunching beats and the venomous riffs carved out by a guitarist dressed as Sid Vicious is undeniable, but you fear that, if the band don't take a serious look at their material, they could wake up one day and find themselves transformed into Jesus Jones.

Predictably they opened the show in Manchester with their latest single, "Smack My Bitch Up", which many have rightly taken to be an endorsement of misogynistic violence. It has to be said that the band do themselves a disservice by dismissing the outrage. After hearing that 35 complaints had been lodged against the poster campaign advertising the single, they merely commented that the campaign was already over, which seems to be missing the point somewhat.

When The Prodigy played the song live, it was accompanied on the video screens by its controversial promo film, in which the camera adopts the perspective of an anonymous protagonist who spends a cheery evening getting drunk, vomiting and assaulting people. The closing shot reveals that this character is actually a woman - a neat way of subverting the traditional male gaze imposed on film, though the point may have been lost on the thousands of people barking "smack my bitch up" at the tops of their voices and can't, by itself, transform the song suddenly into a challenging and provocative piece of work. Its inclusion in the band's show cast a pall over what might otherwise have been a hedonistic carnival of the kind that pop music too often denies itself.