For the prostitutes of Leather Lane, nurse Hester Monk's clinic is a lifeline, providing medicine, food, and a modicum of peace - especially since lately their ailments have escalated from bruises and fevers to broken bones and knife wounds. At the moment, however, the mysterious death of railway magnate Nolan Baltimore in a sleazy neighborhood brothel overshadows all else. Whether he fell or was pushed, the shocking question in everyone's mind is: What was such a pillar of respectability doing in a seedy place of sin? Meanwhile, brilliant private investigator William Monk acquires a new client, a mysterious beauty who asks him to ascertain beyond a shadow of a doubt whether or not her fiance, an executive in Nolan Baltimore's thriving railway firm, has become enmeshed in fraudulent practices that could ruin him.