The City of London, 1678. New Year's Day. Twelve years have passed since the Great Fire ripped through the City. Eighteen since the fall of Oliver Cromwell and the restoration of a King. London is gripped by hysteria, and rumors of Catholic plots and sinister foreign assassins abound.
When the body of a young boy drained of his blood is discovered on the snowy bank of the Fleet River, Robert Hooke, the Curator of Experiments at the just-formed Royal Society for Improving Natural Knowledge, and his assistant Harry Hunt, are called in to explain such a ghastly finding--and whether it's part of a plot against the king. They soon learn it is not the first bloodless boy to have been discovered.
Meanwhile, that same morning Henry Oldenburg, the Secretary of the Royal Society, blows his brains out, and a disgraced Earl is released from the Tower of London, bent on revenge against the King, Charles II.
Wary of the political hornet's nest they are walking into - and using scientific evidence rather than paranoia in their pursuit of truth - Hooke and Hunt must discover why the boy was murdered, and why his blood was taken.