His name, they tell him, is William Monk, and he is a London police detective. But the accident that felled him has left him with only half a life; his memory and his entire past have vanished. As he tries to hide the truth, Monk returns to work and is assigned to investigate the brutal murder of a Crimean War hero and man about town. Which makes Monk’s efforts doubly difficult, since he’s forgotten his professional skills along with everything else.

The year is 1861. The American Civil War has just begun, and London arms dealer Daniel Alberton is becoming a very wealthy man. His quiet dinner party seems remote indeed from the passions rending America. Yet investigator William Monk and his bride, Hester, sense growing tensions and barely concealed violence.

When a maid in the upper class Ellison household is strangled, Inspector Pitt is called in to investigate. He finds a world ruled by strict manners and social customs, where the inhabitants of the Ellison's neighborhood appear to be more outraged by the thought of scandal than they are by murder. Inspector Pitt finds a most unlikely ally in Charlotte, the Ellison's spirited daughter. But as the murders continue, Charlotte and Pitt find themselves drawn together by more than the investigation.

The story opens with the apparently accidental drowning of a sixth form student in the Norfolk countryside. As a matter of routine, or so it seems, the case passes across the desk of Detective Sergeant Smith, recently returned to work after an internal investigation into another case that has led to tensions between officers at Kings Lake police headquarters. As an ex-DCI, Smith could have retired by now, and it is clear that some of his superiors wish that he would do so.

A week's holiday in a luxurious hotel is just what Scotland Yard's Superintendent Duncan Kincaid needs. But his vacation ends dramatically with the discovery of a dead body in the whirlpool bath. Despite a suspicious lack of cooperation from the local constabulary, Kincaid's keen sense of duty won't allow him to ignore the heinous crime, impelling him to send for his enthusiastic young assistant, Sergeant Gemma James. But the stakes are raised significantly when a second murder occurs....