A remarkable story that, like all McEwan’s work, focuses on the inner dilemmas of everyday life. He explodes a single instant into pages of riveting prose—and, like collisions in a cloud chamber, shows how a tiny event can alter destiny.   Although she is a judge, Fiona’s dilemma with young Adam will be familiar to any health care provider who deals with children who have terminal illness. At what age are they able to make decisions for themselves? How much can the state intervene in a parental relationship, especially when stripping them of control will surely do irreparable moral damage for the sake of ends that are by no means guaranteed?   Fiona’s own childlessness and the collapse of her marriage ought to be kept separate from her work on the bench. Yet is that ever really possible?