From the bestselling author of The Rossetti Letter comes a “thrilling” ( Library Journal) novel of intrigue, passion, and royal secrets that shifts tantalizingly between Restoration-era London and present-day Cambridge, England.

London, 1672. A vicious killer stalks the court of Charles II, inscribing the victims’ bodies with mysterious markings. Are the murders the random acts of a madman? Or the violent effects of a deeply hidden conspiracy?

Cambridge, 2008. Teaching history at Trinity College is Claire Donovan’s dream come true—until one of her colleagues is found dead on the banks of the River Cam. The only key to the professor’s unsolved murder is the seventeenth-century diary kept by his last research subject, Hannah Devlin, physician to the king’s mistress. Through the arcane collections of Cambridge’s most eminent libraries, Claire and fellow historian Andrew Kent follow the clues Hannah left behind, uncovering secrets of London’s dark past and Cambridge’s murky present and discovering that the events of three hundred years ago still have consequences today...