November, 1694. The streets of Edo are erupting in violence as two groups struggle for control over the ruling Tokugawa regime. One faction is led by the shogun's cousin and the other by the shogun's second-in-command. Each side would like Sano Ichiro, the shogun's most honourable investigator, to join its ranks. Despite temptation, he remains loyal to the shogun. But neutrality comes with a terrible price, and when a high-ranking official is found brutally murdered, Sano is thrown into another investigation filled with sex and danger and political intrigue.