It was an emphatically creepy affair: murky stage, eerie underlighting, microphones hidden in jaggedy trees and a lengthy set of sparse, spooky tunes.

Crows' Bones was commissioned by Opera North last year and put together with artful imagination by Lau accordionist Martin Green. There were beautiful sounds from his assembled quartet of musicians.

The voices of Inge Thomson and Becky Unthank made a brilliant match: both flat as pancakes (not a wobble of vibrato in earshot), both breathy as mist, Thomson's wan and girlish, Unthank's seductively warm and raspy. Together or in turns they sang of ghost brides and grisly murders, some of the numbers traditional, others (like Jessica Hoop's restless Tulip) contemporary. They tinkered with toy pianos, windup music boxes and metronomes while the bulk of instrumentals came from Green's propulsive accordion lines and Niklas Roswall's chunky drones and twisting, plaintive melodies on the Swedish nyckelharp.

Midway through, a couple of screens were added front-of-stage to show images of rabbit traps and wintry woods – prettily done but totally extraneous in a show that already dealt its atmosphere in spades. If anything, spelling out the visuals had the effect of fading rather than sparking my mind's eye. A far more effective coup de théâtre came at the end, when the lights simply dimmed and we listened to Unthank's haunting a cappella rendition of Banks of Red Roses in darkness.

Something totally different for the evening's first half: Newcastle singer-songwriter Ben Church, whose sweet, boyish warble and dexterous finger picking won him a Danny Kyle Open Stage Award last year. A few striking arrangements stood out, particularly the traditional Searching for Lambs.

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