Obie Trice, Scala, London

The cheerless spectacle of toothless rapping

Eminem's attempt to be Detroit's new Berry Gordy, dragging fellow Motor Town rappers to his own elevated heights, has only been a qualified success. While New York interloper 50 Cent remains a global phenomenon, Shady Records' home-town signings have only diluted Eminem's standing. His latest protégé, Obie Trice, has managed one hit, "Got Some Teeth" (Obie's minimum requirement for a date), but does not have enough to say to fill his Em-produced debut album, Cheers: dramatic enough musically, it is dispiriting in its thoughtless trawl through rap clichés of street violence and scared misogyny.

So my expectations for seeing Obie in person are not high, then, and it's soon apparent that the audience feel the same way. Not quite full for his UK debut, this small north London venue is only politely expectant. And when Obie appears, medium-sized and muscular in a Detroit baseball shirt, his nervous tugging at his trademark beenie hat and look of concentration suggests a man not comfortable with stardom. To compensate, he has brought an immensely fat sidekick to help shoulder the load, which he does with comic skill - looking morally appalled when Obie glugs down a bottle of "brandy", and excitedly singling out anyone failing to put their hands in the air: "Shady gonna kill you!"

Musically, meanwhile, the DJ has one inspired moment, making orchestral soul and hip-hop drums grind against each other like tectonic plates. Otherwise, he concentrates on bouncing beats - Obie struggles to be understood over, making his rapping redundant. With only one album of material, D12's "Blow My Buzz" is meanwhile among the elements dragged in to fill out his set list, as Obie mutters, "Let's keep this moving". Even the teasing promise that "a white friend of mine" has come "all the way from Detroit" only raises mild, disbelieving cheers from a crowd not expecting Eminem-scale excitement tonight.

It is only in the final act that Obie Trice innovates. First tossing the tawdry prize of a Shady jacket into the crowd, with the intention that his male fans fight over it - instead, a woman is knocked down to both rappers' genuine concern - then a dozen girls are then invited on stage in an "ass shake-off" for jacket number two. They soon realise that slithering provocatively round Obie himself will get the best results, as if they have walked into a typically sexist rap video. When the ones Obie does not fancy are ruthlessly culled, it looks more like a groupie audition. And while almost all the girls rise spiritedly to the occasion, it goes on for ever, like a badly run talent show. As the crowd boo their own representatives, it turns into my first reality gig: the audience competing for each other's entertainment. Next time, Obie, try doing it yourself.