You don't expect someone in the crowd to yell "Do some Brel!" at a rock show, but this is by no means an ordinary rock show. "I think we will," says Amanda Palmer coquettishly, and she and partner Brian Viglione tear through an alternately delicate and riotous version of Jacques Brel's Amsterdam.

Palmer, who looks like a dishevelled Lulu - that's Wedekind's Lulu as played by Louise Brooks, not the diminutive Scottish yelper - and Viglione, dangerously pretty, stripped to the waist, in makeup, are a distinctly peculiar proposition. An American piano and drums duo signed to Roadrunner, a metal label, and playing here in a goth/metal club, they draw on an array of interrelated things - Weimar-era cabaret, torch song, German Expressionism - to produce an often bawdy, consciously melodramatic music of heightened emotions that also exploits a rock dynamic. It's a hybrid with little precedent save, perhaps, Bowie's dalliance with Brel and Kurt Weill, or the Sensational Alex Harvey Band's unexpected take on Brel's Next.

Both Palmer and Viglione are extremely able musicians, but they're also partial to bashing nine shades of hell out of their instruments with a gleeful lack of sophistication, as in their rollicking and timely cover of Black Sabbath's War Pigs.

But songs such as Mrs O, in which Palmer plays the role of a deluded woman who denies the Holocaust, are subtly crafted exercises in subversion. Palmer's voice is a low purr that's often reminiscent of Nico, perfect for this kind of material and most pronounced on a lovely strum through T Rex's Cosmic Dancer. For all the artfulness, though, there's something sweet in her simple, entirely Wayne's World appreciation of the audience as "fucking awesome".

· At Cambridge Junction tonight (01223 511 511), then touring.