This is a tense portrayal of a mystery in Martin's past, and its effect on his life and relationships - chiefly between him and his wife, Jennifer, and another couple, Stephen and Jacqui. The main themes explored in this novel are the impact of a single traumatic event on the life of an individual, the fragility of friendship, the effects of aging and changes in personality on relationships, and the impact of class origin and childhood upbringing on later life, all played out in the seeming tranquility of the Yorkshire Dales.