Every night Hester Monk tends to women of the streets who have been injured as a result of their trade. But the injuries are becoming more serious, and now a body has been discovered in one of the area's brothels. The dead man is the respected head of a successful railway company, Nolan Baltimore. With calls for the police to clean up the streets, Hester decides she must intervene to protect these women who stand to lose everything. Meanwhile her husband, William Monk, is investigating a possible fraud at Baltimore and Sons. As Monk endeavours to prevent a serious crime from taking place, he faces some staggering revelations, and finds that the time has come to confront his own demons - even if it means losing all he holds dear...