In Parker's compelling fifth mystery set in feudal Japan (after 2007's Island of Exiles
), Sugawara Akitada, now a senior secretary in the ministry of justice, suffers guilt over his failure to fulfill his promise to Haseo, a recently deceased convict who saved his life in an earlier book, to exonerate him. As Akitada makes some small progress toward finding the truth about the five-year-old murders Haseo was blamed for, he must also clear his own retainer, Tora, of the murder of a blind street singer. His inquiries on both fronts come at a time of increasing tension with his wife, Tamako, and as an outbreak of smallpox disrupts the capital city, Heian-Kyo. A capricious and unreliable boss, Soga, adds to his woes. Besides smoothly mixing action and deduction, Parker gives her protagonist an emotional depth that raises her to the front rank of contemporary historical writers, including Laura Joh Rowland, the author of a similar series set in 17th-century Japan (The Fire Kimono
, etc.). (Aug.)