Dizzee Rascal, Electric Ballroom, London

New heights for Rascal on a roll

Dizzee Rascal saunters on stage sporting the infectious grin of a boy who feels that every day is Christmas. Though he starts with "Sittin' Here", the opening of his Mercury-winning debut Boy In Da Corner (2003), which details his oppressively intense, near-catatonic state on a typical day on his old East End council estate, his life has moved at warp speed since writing it.

Boy In Da Corner sounded almost frightening when it arrived, welding squelching jungle bass to the helium raps of a boy whose voice seemed barely to have broken. The astonishing quality of the then 18-year-old Dizzee's production, with its whistling cyber-chimes and pizzicato strings, could not mask the record's clammy mixture of fear, aggression and yearning, describing an emotional state too near the edge to allow relaxation or trust. It was a true transmission from Dizzee's own burning brain. It was also from the council-estate life that still suffers from a cultural apartheid in Britain, examined from a distance as a problem or jeered at as the preserve of "chavs", but otherwise invisible.

Dizzee was one of the first to give this Britain a voice. Equally importantly, he was not confined by it. Influenced by grunge as much as grime, Sham 69 as well as So Solid Crew, he was a musical omnivore, unwilling to conform to a scene's clichés. While US rappers lazily brag about "keeping it real", Dizzee's lyrics on his second album, Showtime (2004) suggested he had more in common with Sixties working-class heroes like Michael Caine: not forgetting his roots, but eager to show a way out to a wider world.

Dizzee is on stage at this Camden club with just a fellow MC (who soon loses his voice) and a DJ. When bulbs burst into light for "Learn", that's it for visual stimulation. It's lucky, then, that Dizzee's teen apprenticeship at raves and pirate radio stations has honed his stage-craft to an enviable edge. Where most American rappers treat gigs as dope-paced, cliché-packed chores, Dizzee is in constant motion, working to find ways to connect. That eager grin rarely leaves his face, and the flow of words and music never stops. He raps at a speed anyone five years older than him may find incomprehensible, without misplacing a syllable of his intricate lyrics. On "Respect Me", the words are so fast they are squashed into stabbing consonants, as if someone has flicked a dial in his head into the red. But still, the bragged meaning blasts through.

"Where are all the people who are ready to cut loose in public ?" he asks, but this crowd are painfully repressed, shuffling their feet as if at an indie disco. When he later asks how many are from council estates, and a dozen or so hands go up, his Mercury-induced move upmarket explains the sloth. These new fans are not as desperate for a night out as Dizzee is. Undeterred, he teaches them some grime phrases, happy to build a broad church. He then offers a new rallying point, to "anyone who's been through hard times" - "Get By", the Showtime song that bridges his old life of trapped fear and new one of apparently infinite hope.

"Thugs talk murder/ and they live by their word," he raps. But amid this pressure, there's a dreaminess, the wistful imagination that lets him survive: "Sometimes I feel so high/ looking at the sky".

Vanya's sampled female soul vocal adds another layer of warmth. As he calls out to every corner of London, there's a feeling of inclusive community that demolishes the boundaries that once imprisoned him. In somewhat pantomime style, he has to be literally dragged from the stage during the closing "Stand Up Tall", by which time heads are nodding furiously everywhere. The shock of the new is no longer on his side. But Dizzee looks like he will be here for a while.