It is 1550: a time of divisive political, economic, and religious innovation throughout England. Although the City of London is burdened with overpopulation, poverty, and crime, so far its watch and constables have managed to keep the peace. However, when the body of an unidentified man is discovered in the butcher's district, brutally murdered with a meat cleaver, tension between the City's butchers and its rising immigrant population threatens to escalate into violence.
Under pressure from sheriff Sir John York to find the murderer and restore order, parish constable George Harwood enlists his friend, soldier-turned-innkeeper Thomas Whyte, into the investigation. Unwittingly, he also involves Katherine Whyte, Thomas's strong-minded and capable cousin. The three unlikely detectives follow a trail of suspicious deaths, from the affluent mansions of Walbrook to the slums of Fenchurch Street. But are they connected? What part do York's own shadowy dealings play in the drama? Is there a political dimension to the deaths, or are they just the result of the random casual violence that typifies City life?
As the investigation proceeds, Whyte finds himself increasingly drawn into the unfolding series of events, making powerful enemies, and putting his own life and Katherine's in jeopardy.