You wait ages for one exceptional novel set in Wales during the second world war to come along, then two arrive hot on each other's heels. After Peter Ho Davies' The Welsh Girl comes Resistance by poet and first-time novelist Owen Sheers. Although the two books are markedly different (in Sheers' story, D-Day fails and Germany invades Britain), they have much in common: both revolve around a relationship between a Welsh woman and a German soldier; both combine lyrical prose-poetry with a compelling plot; and both are well crafted. It is September 1944 and Sarah Lewis awakes to find her husband Tom has disappeared, along with most men in the Welsh valley. When one night she cries out his name, she is startled when a man responds - not her husband, but a German officer called Albrecht. So begins a relationship that subtly blurs the line between occupier and occupied. Many writers have used this counter-factual 'what if' as the basis for a thriller - Robert Harris in Fatherland, for example. So does Sheers, after a fashion. But his real aim is to allegorise a time and place that until recently has rarely been considered: a Welsh homeland robbed of a generation of men. Resistance is a remarkable achievement from a most promising writer.