To look at the history of socialist writer Barry Hines’s classic 1968 realist novel A Kestrel for a Knave’s relationship to the stage is to see a typically bourgeois medium struggling to make something rather upsetting more palatable for its audience, like an oyster turning a rough grain of sand into a smooth pearl, lest it be allowed to sink in and do damage to its system. Conventional wisdom has it that cinema is better for naturalistic realism than the inherently more poetic stage, and comparing Ken Loach’s 1969 film adaptation with the various theatrical ones there’s been, including that apex of escapist forms, a musical version, won’t dispel that theory. That said, it takes more than a bit of pomp to destroy the source material’s enduring power.

Butler draws us into Billy’s inner-world with an honest, raw and moving lead performance

Set in Barnsley in the late sixties, fourteen-year old Billy Casper (Stefan Butler) finds respite from his harsh existence, including his bully brother Jud (Oliver Farnworth) and a parochial school system set to pigeonhole him into a dead-end job, in his relationship with a kestrel he finds on a farm. But can such a delicate thing exist in his oppressed and oppressive working-class environment?

Making Kes without the kestrel might seem like trying to make a folk song without lyrics, but Lawrence Till’s adaptation largely manages to make the story work without it, helped by Butler drawing us into Billy’s inner-world with an honest, raw and moving lead performance. But it’s typical of director Nikolai Foster’s production to substitute the bird, a natural and implicit metaphor for Billy’s inner-spirit, with a highfalutin, balletic dancer swooning around the stage (perhaps also inspired by the magpie-ing Billy Elliot, which also swapped the bird for ballet), that couldn’t be more out of touch with the tone of the source material. But even if the issues of class are uncomfortably bound up with an aesthetic symptomatic of an ideology that helps breed such issues, it’s still a poignant celebration of individuality rising above the oppressiveness of an individualist society.

King’s Theatre, until Sat 31 Oct