Dizzee Rascal, Shepherds Bush Empire, London

Dizzee Rascal's struggle to stretch out and show his full creative range, without snapping the bond to his roots, will define how he is remembered. His Mercury-winning debut, Boy in Da Corner (2003), remains UK hip-hop's pinnacle, and his career already dwarfs every other British rapper's. But Dizzee's move from a Bow council estate to an English country home, and the presence of Alex Turner and Lily Allen on last year's Maths + English, shows the bigger picture he has always understood. "World Outside" opened that album, repeating the assertion of Showtime (2004) that pride in the "ghetto" background he carries inside him would not stop him rising from it.

This borderless creative curiosity burned in Dizzee as a teenager, when Nirvana's In Utero was a touchstone. But he is treading water musically now. The English country-grime concept album of my imagination will have to wait; Maths + English is a slicker gloss on past glories.

This NME Awards gig shows he retains a strong audience. The grinning, undisguised joy of dreams coming true that once defined his live performance has been replaced by a quieter, more professional presence. But "Paranoid" soon slips into the introspection that sets him apart from US rap stars. "Use me out, rinse me out, cross me out," he raps with effortless, rolling speed, over DJ Semtex's fittingly dub-heavy bass.

As with "Bubbles" and its unconvinced, ambiguous immersion in the champagne lifestyle beloved of rap videos, doubt is Dizzee's secret weapon. There, too, his precisely rhythmic double-rapping with his co-rapper is superb. He still lets Semtex's abrasive scratching and deepening beats swallow his words. Partying, not preaching, is the point.

"Jus' a Rascal", Dizzee's 2003 calling card, and 2004's "Fix Up, Look Sharp" both recall the helium-high, hectoring tone that made him such a fizzing thrill, before the narrative of violent street-crime in "Sirens", accompanied by footage of him being chased through council estates by huntsmen, kicks in. But you wonder if he can square the circle between how he heard those sirens in his brief spell as a teenage mugger, and the vicarious thrill most of this crowd take from them.

"Are we in the Isle of Wight?" Semtex wonders of the quiet, before these fans finally holler back. The grime-disco of Dizzee's new Calvin Harris collaboration "Dance With Me" shows he still wants to push boundaries. Whether he still has the nerve and drive he arrived with, sufficient to shatter genres and audience ghettos, time will tell.