Dizzee Rascal, Koko, London <!-- none onestar twostar threestar fivestar -->

Dizzee Rascal, the boy from Bow, knows how to work an audience and that's hardly surprising, considering he supported the Red Hot Chili Peppers on their 2006 European tour, and has also opened for Pharrell, Nas, Jay Z and Sean Paul.

His MySpace blog promises that tonight's gig will include a full set of Maths & English, his just-released album.

There's no tedious dallying between support and main act, and no introduction either: Dizzee - white cap cocked to 3pm - catches Koko off-guard and explodes on stage with two of the most well-known songs from his 2003 Mercury-winning debut album, Boy In Da Corner. Nearly five years on and the bizarre operatic chorus of "Just a Rascal", and the single that got the teenage tearaway a record deal with XL, the lurching, adolescent battle of the sexes "I Luv U", still sound raw, like rap from another planet.

Dizzee puts more energy and effort into the first five minutes than you usually see in an entire hip-hop concert. The downbeat, metronomic delivery of "Paranoia" (chorus: "They want to rinse me out, use me up, cast me down, fuck me up"), acts as a breather alongside the radio-friendly Alex Turner collaboration "Temptation".

There are no surprise guests tonight, such as Turner, Lily Allen and the H-town (Houston) gangsta rappers Bun B and Pimp C, all of whom guest on Maths & English. The focus here is squarely on Dizzee, who basks in the spotlight: at Koko he is utterly at ease, prowling, dancing, shadow-boxing and surveying the crowd as he raps.

He's wearing a Dirtee Stank (his own label) T-shirt, in line with hip-hop's entrepreneurial, self-promotional spirit. The T-shirt soon comes off, revealing a washboard stomach.

"Dreams", sampling Captain Sensible's 1982 hit "Happy Talk", turns out to be a gimmicky, weak moment. And it's as if Dizzee realises this, as, midway through the song, he commands his DJ, Semtex, to "fuck that shit", and launches into current single "Sirens". Its intricacies are lost on the PA and the song is reduced to a mix of cymbal, bass and panted lyrics, which sound delivered on the run, but its impact shatters the slumber.

The classic New York boom-bap beat and Dizzee's squawky, halting delivery on "Fix Up, Look Sharp" maintains the fevered momentum, and the night lifts off when Semtex introducesFat Joe's 2004 anthem "Lean Back".

"Da Feelin", a track made with leading drum and bass producer Shy FX, comes across as formulaic, and a disappointing waste of potential. The baiting in "Pussyole" of Dizzee's former mentor Wiley (Dizzee's debut LP liner notes read "Shout out to da one and only Wileykat - I love you like a brother") thankfully gets lost in the song's sampling of old school hip-hop, including Rob Base and DJ Ez Rock's "It Takes Two".

Dizzee's encore sees him joined on stage by his warm-up act, the grime trio Newham Generals (signed to Dirtee Stank - note again Dizzee's cunning product placement), and the comedic grime MC Jammer, for a track "for the smokers" - a cover of "Puff the Magic Dragon", a song that never made Maths & English's final cut.

It's a suitably light moment, which will soon become an anachronism with the imminent smoking ban, before the serrated electro of "Stand Up Tall" offers a rare, true grime moment: six MCs barking over a tumultuous instrumental as a sweating, breathless audience bays for more.

Dizzee has managed to inject the intensity of a full-blown rave - drawing on his roots in garage - into this compelling and confident performance. Considering that he is not yet 21, Dizzee's grasp of gig dynamics is as thrilling and impressive as his music.

Dizzee Rascal is appearing at The Junction, Cambridge (01223 511511) on 21 June