London, 1678. The blood-drained body of a young boy is discovered in the snow on the bank of the Fleet River. The city, overlooked by the exhumed head of the Lord Protector Oliver Cromwell, teeters on the brink of riot and hysteria, with rumours of Catholic plots, devil-boys, and sinister foreign assassins. It is twelve years since the Great Fire ripped through the heart of the city. Robert Hooke, natural philosopher and Curator of Experiments of the Royal Society is an architect of the rebuilding. Hooke and his assistant, Harry Hunt, reluctantly agree to investigate the murder of the bloodless boy after instruction from King Charles II. Harry, ambitious and wanting to prove himself as an able natural philosopher, and to break free from the shadow of Hooke's brilliance, takes the lead in investigating the death of the boy. He finds a sinister tale with roots in the dark past of the Civil Wars. As he gets closer to finding the use of the bloodless boy, he uncovers the terrible consequences of experiments performed in the name of the New Science.