Soon after Waterloo, Lady McInnis and her daughter are found murdered in Richmond Park, their bodies arranged like figures on medieval tombs. The staging repeats the unsolved murder of magistrate Henry Lovejoy's wife and daughter fourteen years earlier, for which a traumatised former soldier was hanged.
Sebastian and Hero investigate the McInnis household, a wounded Waterloo veteran, a musician and people involved in the exploitation of poor children. When suspicion approaches a favourite illegitimate son of the Prince Regent, palace pressure increases and the possibility that an innocent man died for the earlier crimes becomes impossible to ignore.