In London of 1840, the economy is sliding into recession; gangs of unemployed workers roam the streets; and a murderer prowls the capital's poor neighborhoods. Pyke, still grieving over the death of his wife and struggling to shoulder his responsibilities as a father, is in debtors' prison, having lost his home and reached the edge of bankruptcy. Fitzroy Tilling, now head of the new Metropolitan Police Force gives Pyke his freedom, but in return he must agree to investigate the brutal death of a young biracial woman, who was apparently working as a prostitute. It is not long before another woman turns up dead, and Pyke begins to suspect that he has stumbled on something more sinister, and more far-reaching than the murder of a couple of prostitutes. Pyke's investigation takes him from the London docks to the sugar plantations of Jamaica, from a fading colonial mansion to the backstreets of the East End in a struggle against ambitious and ruthless enemies, as well as demons of his own.

It is 1835, and with the birth of the Industrial Revolution, railway fever sweeps the country. Pyke is uneasy with the luxury his aristocratic marriage has brought him, and when he is unofficially asked to investigate a decapitation, he can not resist the chance to resuscitate the old skills he learned on the streets. But with the industrial world comes a new and faceless enemy: men who have money and power, and who will stop at nothing in their pursuit of both. For Pyke, with his young wife and child and an elevated place in society to protect, the stakes have suddenly become alarmingly high. From the sweat shops of the east end to the palace of the Queen-in-waiting; from the elegant drawing rooms of the newly rich, to the blood-spattered backrooms of London's taverns, Pyke's investigation stirs up a hornets' nest of trouble. As the death toll rises, an alluring woman from his past returns, Pyke must draw on all of his resources if he is to protect his family, and survive.