Mick Jones has been at the helm of three great bands: the Clash, sampler pioneers Big Audio Dynamite and, as producer, the Libertines. However, Carbon/Silicon are his first new outfit in two decades, after two life-threatening illnesses drove him away from music. His reappearance in a quartet with Sigue Sigue Sputnik's Tony James sparks religious fervour in an audience of Pete Doherty fans, beery blokes and one mohican so venerable it should carry a plaque from English heritage.

Jones steps on stage looking cooler than them all, wearing a trilby the Libertines liberated from the Clash's Sandinista period. However, he whips off the titfer to reveal a balding pate. "It used to be a quiff," he quips, before addressing the flock. "If anyone's got a glass eye you might wanna tap along."

The guitar shapes are ironic now, the punk sneer replaced by a grin, and his new guitar style sounds like Captain Beefheart's guitarist falling down a flight of stairs. The chord structures and lines such as "What use is ambition if a man loses his soul?" could be the Clash if they'd grown up with iPods and Dizzee Rascal. Perhaps the lyric reveals why Jones has partly stepped out of the game.

MPFree proudly articulates CSi's embrace of free downloading, but I Don't Know is innocuous piffle about a cab driver. When Jones confesses "We don't really do rehearsals", a song collapses. However, out of near fiasco emerges the old fire. Really the Blues, a vaguely Bowie-like stormer, leads into Gangs of England, cut from the same cloth as the Clash's Guns of Brixton. By the closing Network, Jones is blasting off about individualism and societal control like a man who has nothing to prove but still has something to say. It's not a case of whether Jones has another great band in him, just whether he wants it.

· At the Barfly, London NW1, tonight. Box office: 0870 907 0999. Then touring.