Folk singer Alisdair Roberts comes from a long line of Scottish gamekeepers. It is clear he made the right career choice: he doesn't seem the outdoor type. He is tall and painfully thin. His face has an expression of bitter disappointment. Sporting sideburns and a patterned tank top, he looks not unlike a minor character from Rising Damp.

The severity of his appearance also gives him the air of an undertaker, which is appropriate. It is hard to think of another songwriter whose material has a body count this high. His opening number, Two Brothers, gives notice that no scenario is too innocuous to support a guest appearance from the grim reaper. One minute two schoolboys are happily chatting, the next one has been stabbed to death.

The mortality rate lends his songs a riveting edge. Every time his exquisitely lugubrious voice mentions someone by name you think: uh-oh. "See Polly," he sings, "singing as she sits at her spinning wheel." You immediately become concerned lest the wheel become detached and she ends up with her bonny wee head cleft in twain.

But it is not just morbidity that makes Roberts a gripping performer. Visibly nervous between songs, he seems transported when the music begins. And with good reason: backed by a guitarist, a wheezing analogue synthesizer and a drummer who at one point starts thumping the kit with his bare knuckles, his sound is at once eerie and immediate, steeped in a history most rock artists ignore, yet entirely of the moment. As he encourages the audience to hum along while he mournfully dispatches another unfortunate character, the sense you are witnessing a unique artist is, like the bony hand of mortality in his songs, impossible to shake off.