London, 1591: Nicholas Shelby, physician and reluctant spy, returns to
his old haunts on London's lawless Bankside. But, when spymaster Robert
Cecil asks him to investigate the dubious practices of a mysterious
doctor from Switzerland, Nicholas is soon embroiled in a conspiracy that
threatens not just the life of an innocent young patient, but the
overthrow of Queen Elizabeth herself. With fellow healer and mistress of
the Jackdaw tavern, Bianca Merton, again at his side, Nicholas is drawn
into a sinister world of zealots, charlatans, and dangerous fanatics.