For all his talk of conspiracy theories and creatures from outer space, one flight of fancy Matt Bellamy hasn't attempted is convincing anyone that beyond his space geek persona lurks a lusty sex symbol. Yet here he is, rolling his hips against his guitar like a lipsticked lovely in a Robert Palmer video, his overwrought falsetto a saucy coo that would make Prince blush.

Maybe the intimate surroundings have lit a fire within Bellamy. Muse are festival headliners, not cosy entertainers, as Bellamy reminds us in a rare moment of conversation. "Some of my gear's knackered," he says. "It got rained on the other day."

Used to open spaces, the volume is turned up to a Spinal Tap-inspired 11. Every thunderous riff is at a deafening pitch. Confining their preposterously grandiose songs in a building with a roof, however, doesn't squash the band's huge sound - it just pushes every ludicrous twist and turn to breaking point.

Under close scrutiny, Bellamy's elegant posturing appears ever more outlandish. Dressed in a black shirt, jeans and white braces, he follows the instructive lyrics of Take a Bow then thrusts an arm in the air, playing the rock god as victorious hero.

Muse make music that shouldn't work - the intro to Time Is Running Out recalls the Knight Rider theme tune, for example - and turn it into dirty rock opera. The brittle epics Plug in Baby and New Born burn beside the eclectic aural assaults of new album Black Holes and Revelations. Supermassive Black Hole, the sound of funk and electroclash meeting on a dark dance floor in Mars, swells and seduces, while the literally galloping optimism of Knights of Cydonia provokes crowd salutes straight from Queen's Radio Ga-Ga video.

With their opulent thrills, unrelenting tension and cosmic madness, the universe is Muse's for the taking.

· At T on the Fringe, Edinburgh, on August 24. Box office: 0870 169 0100