Speaking is tricky, moving nearly impossible. The crowd gathered under Oxford Street gape silently, sweat pouring down every face and glistening in the dark. In fact, it's so damn hot in here the band is the last thing on everyone's mind. It's a shame, because Dublin trio JJ72 are worth all our attention.

Since leaving school last summer, they've been quietly causing a stir over here. Not hogging the airwaves and talking up a fight with the papers, you understand. This is a silent, deadly revolution which may take more time than the other Next Big Things but will ultimately matter far more.

Tonight, JJ72 emerge as a band who are finally ready for it all. Since their early gigs in London, they've toughened up and almost quiver with confidence onstage; something which makes them quite wondrous to watch tonight.

To our right, calmly aloof bassist Hillary Woods stands tall, all pouts and cheekbones, hair wet with sweat and black eye make-up smudged carelessly. She barely acknowledges the crowd and never utters a word, she's JJ72's secret weapon, adding the same touch of mystery and glamour Charlotte Hatherley brought Ash. She's the dose of reality to singer Mark Greaney's wild, untempered emotion.

Though appearing as shy and endearing as they come, during 'Oxygen', he sings like he's been chewing sandpaper. His plaintive, husky wails are a haunting echo of Kurt Cobain and that infamous Unplugged session and likewise, despite the looks, he sounds utterly despairing and - at times - livid, as he growls despondently. But it's dangerous to feel too settled with JJ72. By 'Broken Down', Mark's incredible falsetto is echoing round the room, as ethereal as Jeff Buckley with Woods' tough, thudding Joy Division-esque basslines only emphasising the fragility.

By the end, each band member is frowning with concentration, bent over their instruments and teasing out every last bit of feedback. And in an instant, they've gone. No encore, no goodbye. JJ72 want you begging for more. Expect a mission accomplished.