Unsettled by the death of his mother, Paul sets out for London in search of Pia, his daughter from his first marriage. Discovering her pregnant and living with a pair of Polish siblings, Paul is entranced by Pia's life on the edge. Abandoning his second wife and their children in Wales, he joins her to begin a new life. Cora, meanwhile, cannot stay with her decent Civil Service husband, and she hasn't fully come to terms with herself. Connecting both narratives is the London train, and in this novel by the author of Married Love and Other Stories, a chance meeting will have immediate and far-reaching consequences for both Paul and Cora.