As commander of the River Police, William Monk is accustomed to violent death, but the mutilated female body found on Limehouse Pier one December morning moves him with horror and pity. The victim's name is Zenia Gadney. Her waterfront neighbors can tell him little -- only that the same unknown gentleman had visited her once a month for many years. What sinister secrets could have made poor Zenia worth killing? And why does the government keep interfering in Monk's investigation? While the public cries out for blood, Monk, his spirited wife, Hester, and their brilliant barrister friend, Oliver Rathbone, search for answers.