The murder of a prostitute named Ada McKinley in a bedroom on decrepit Pentecost Alley should occasion no stir in Victoria s great metropolis, but under the victim s body, the police find a Hellfire Club badge inscribed with the name Finlay Fitzjames a name that instantly draws Superintendent Thomas Pitt into the case. Finlay s father immensely wealthy, powerful, and dangerous refuses to consider the possibility that his son has been in Ada McKinley s bed. The implication is clear: Pitt is to arrest someone other than Finlay Fitzjames for Ada s demise. But Thomas Pitt is not a man to be intimidated, and with the help of his quick-witted wife, Charlotte, he stubbornly pursues his investigation one that twists and turns like London s own ancient streets.