This time, Sano was assigned to a sensitive murder investigation more than four decade old involving a member of the Tokugawa clan, cousin to his lord Shogun Tokugawa Tsunayoshi. The murder apparently occurred sometime during the historical Great Fire of Meireki the destroyed much of Edo city that took the lives of many people in the confusion. Sano was shocked when his mother became embroiled in the case as a primary suspect and learned there were much more to her than he had ever imagined.