First Night: The Strokes, University of London Union, London

The Strokes were always an unlikely bet for rock'n'roll's great hope. They have never stood for anything in particular, or said anything worthwhile. Their sound was nothing new, borrowed from the late Seventies punk heyday of New York.

Listened to four years on, their lauded debut, Is This It, sounds less like a call to arms than a narcotised shrug, with occasional bursts of energy. Where Kurt Cobain's grunge generation sometimes seemed to complain about nothing, Strokes singer Julian Casablancas couldn't even be bothered to do that.

And yet, somehow, The Strokes kick-started the guitar rock revival. Part of it was their model good looks. But most of it was a stack of brilliant tunes they sounded almost too bored to deliver.

Their second album, Room On Fire, had as many as their first, more ammunition for the Greatest Hits that will be their lasting glory. But indifference to advancing their sound cost them, leaving them looking foolish as The White Stripes and others marched past.

So their upcoming (much improved) third album may be make or break for The Strokes. And tonight's comeback gig may decide which one it will be.

They come on, late, with neon-haloed hair. An army-jacketed, shade-masked Casablancas pauses to converse with the fans in front, teasing them with close-up star quality. Then they kick into raucous new single "Juicebox'', and the comeback has begun.

Between songs, Casablancas sounds fashionably, inarticulately slurred. The first batch of new songs are similarly drifty, stoking up little passion in the crowd. "Vision Of Division", an amphetamine-abused reggae riff stapled to a soaring, impatient chorus, follows, a timely sign that The Strokes are still a rock'n'roll band.

"Razorblade" is soon heisting Barry Manilow's "Mandy" for its chorus, with shameless finesse. "I don't feel what you feel," Casablancas sings soon afterwards, summing up his new lyrics' mood of disaffection. What follows alternates between slurred, drifting introspection, recalling the heroin haze of New York rock's most decadent years, and raw aggression that suggests just the opposite.

"This is our last new song,'' Casablancas promises before "You Only Live Once"'s rolling optimism. From then on, it's a Strokes jukebox. "Last Nite" and "Someday" punch past to applause, dancing and happiness, though no hysteria. People seem unsurprised to see them back in a packed club, as if it's their natural home. "Take It Or Leave It", one of their finest songs, is followed by "New York City Cops", an anti-police rant suppressed in the US post-9/11, but here the ignition for final abandon in the crowd. By "Reptilia'', the fans have lost it. And the Strokes, after all, still have it.