For the prostitutes of Leather Lane, nurse Hester Monk's clinic is a lifeline, especially welcome 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. Meanwhile, brilliant P.I. William Monk acquires a new client, a mysterious beauty who asks him to ascertain whether her fiancÔe, an executive in Nolan Baltimore's thriving railway firm, has become enmeshed in fraudulent practices that could ruin him.