Bat for Lashes, Roundhouse, London

(GETTY IMAGES)

When Natasha Khan asks "shall we carry on with a bit more dancing?" she might as well be talking to herself. The trademark cape has a bit more sparkle than previously, but tonight's audience is not looking for a big pop performance. They stand in awe as she powers through the best of Fur and Gold and Two Suns.

While Florence Welch glammed her way around the Shepherd's Bush Empire in silk and flowers last week, under the Roundhouse's circus top there's no need for a flashy stage show. Khan uses her multimedia education. It's easy to see how she's inspired by the visual art of Susan Hiller instead of stadium theatrics. Neon lamps, flashes of lightning and swirls of atmospheric fog are slowly revealed and mirrored backdrops surround her as she sits at the piano. Forming a protective circle, it's as if she wants her cave back, a safe place to just sit and sing to her own reflection. At moments, she's back at number 48 in the charts, playing to 100 super-fans at a Brighton club. They transform into eerie landscapes when her vocals start to soar and the band kick in, emphasising the earthy aesthetic of Bat of Lashes' entire set. The only machine she wheels out is a beaten-up TV to complete her duet with Scott Walker, "The Big Sleep". When she throws off her cape halfway through, swapping big heels and glamour for bare feet and a bodysuit, it's no surprise. It isn't even a costume change. "It's warm up here," she explains.

Yet the show isn't entirely free of popstar shtick. The Kate Bush claw makes more than one appearance and, as ever, it looks a little forced. The musical comparisons are more than justified but Khan doesn't need to contort her body in homage to her idol. The wind-machine is just a step too far. Forget Bush, super-diva Bonnie Tyler copyrighted that move. A fun trick in theory, but as she squints into the breeze she looks uncomfortable. Thankfully, it's only turned on for two songs, and even then she seems loathe to step into its path. Khan's natural energy, tiptoeing and bowing in a shamanistic ballet, is far more impressive than the hand gymnastics of younger female singer-songwriters from Pixie Lott to the ex-X Factor contestant Diana Vickers.

Like the staging, her music is best when it stays simple. The vocals twinkle as delicately as the fairy lights that surround her, blasting into thumping sections that highlight the influence of tonight's "psych-snap" support Yeasayer on her newest work. Those who are impressed by Khan's confident rhythms will fall in love with "All Hour Cymbals". Bent over double and wailing on "Siren Song", she's breathtaking, effortlessly bringing the dual personality of her latest album to life.

If the Mercury judges missed something, it would be how the album embraces mainstream and alternative styles, packing big choruses ("Daniel") alongside her waif-like solos. Yeasayer's production lets bass and beats dominate on other songs, referencing time spent getting wild with friends in a New York club. Even older material is effortlessly reworked; "What's a Girl to Do" and "Priscilla" get the biggest cheers of the night when they are transformed into fierce harpsichord ballads.Leaving the stage with a few coy thank yous, it's clear what Natasha Khan is going to do. Forget dancing, she's quite happy, just standing, on her own two (bare) feet.

On tour (www.batforlashes.com)