Smoke Fairies, Scala, London

Smoke Fairies is a particularly apt name for this pair of Jack White-signed guitar ladies. An allusion to the mist that collects on Sussex hedgerows, it perfectly encapsulates the ethereality of their work.

Their interplay is divine, with songs built from two simple guitar lines woven intricately together, swathed in breathy vocal harmonies. It's southern gothic at a very quiet ebb, a kind of Cocteau Twins without embellishment, or a Mercury Rev in sackcloth and ashes.

Despite the self-evident beauty of their music though, Smoke Fairies' reputation as rather motionless performers remains intact. There's plenty of dry ice and a fetching projection of a dead tree behind them, but it's not quite AC/DC.

Rock shapes are hardly necessary, however, when the harmonies are as heaven-sent as these. The weft of their voices is even lovelier live, and they use the room's acoustics to haunting effect – a shared playing career stretching back to school in the late 1990s has paid ample dividends in terms of unity of purpose. The effect is otherworldly at times; they are both individually talented singers, but together they create some glorious effects without ever seeming to try. It raises the question of what they'd be like if they dared to push themselves and sing more oppositionally. They do it a little once, on "Strange Moon Rising", one of them chiming in with a sudden startling counterpoint to the other, but it's an effective technique woefully underused.

The band themselves – Katherine Blamire and Jessica Davies – are beautifully endearing, two long-toiling musicians thrust suddenly into the limelight late in their career, enjoying it and bewildered by it at the same time. Both have a sweet line in bashful stage humour, confessing to being full of whiskey to calm the nerves, and admitting that venues with dedicated sound guys are still a novelty. Amazing what an endorsement from one of the most famous musicians on the planet can do for a career, really.