Here, Perry, whose past novels have featured Inspector Thomas Pitt and wife Charlotte in Victorian era London (Bethlehem Road, etc. etc.), uses the same setting but a different lawman in this outing. He is William Monk--a well-spoken, aloof, unpopular police detective--who has survived a severe accident with bones healed but memory gone. Quickly becoming aware of a bitter rivalry between himself and his superior Runcorn, Monk decides to keep his amnesia a secret, even from sympathetic young aide John Evan--and even when he finds himself in charge of the recent savage murder of Major Joselin Grey, third son of the aristocratic Shelburne family and a hero of the Crimean War. True, the major seemed to live in a style well above his sparse family allowance, but Monk, trying to renew his old, vaunted detecting skills, can find no evidence of illegalities. Meanwhile, Monk's private life seems to have been bleak and lonely, but a chance encounter with delicate, gentle Imogen Latterly produces an emotional response in him. He discovers that she had appealed to him to investigate further the seeming suicide of her father-in-law after the death of a son in Crimea and after losses in a new business venture. In the end, these seemingly unrelated events come together, helped along by Imogen's tough-minded sister-in-law Hester, who had nursed in the Crimea, and by Monk's slowly returning memory. They form a complex but convincing denouement in a story at times long-winded and repetitive, but richly textured with the sights and sounds of London and its countryside; the rigid social structures of the well-born; the abysmal misery of the poor and haunting echoes of the slaughterhouse that was Crimea. Solidly absorbing and Perry's best to date.