Rappers who hit the big time are usually faced with a moral dilemma. After all, flashing lights and movie premieres make it all too easy to lose the working-class vibe that gives their music its street-cred in the first place. Which is probably why Dizzee Rascal, winner of last year's Mercury Prize for his superb debut album, spends half of the follow-up reassuring us that he hasn't forgotten his roots and that he'll never leave the grimy streets of east London. As admirable as this is, it all gets a bit repetitive after a while, and you can't hep feeling that the 20-year-old wunderkind is starting to run a bit low on ideas. Luckily, his brutally minimalist beats are just as thrilling this time around, while his curiously yelping vocals give his quickfire rhymes a moral authority far beyond his tender years. With that difficult second album out of the way, his future progress should be fascinating to watch.