Slaves and obsession

In the American Civil War, the opposing armies are desperate for arms. A London trader selling weapons to the South faces a moral dilemma when his daughter, in love with a Confederate, insists he change sides. When the trader is brutally murdered, her lover is suspected and justice is sought. Ritual murder, mysterious disappearances, and theft spur Victorian investigator William Monk and his wife Hester to investigate an arms dealer and his seemingly flawless London mansion.