In the year of our Lord 1363, two suspicious deaths in the infirmary of St. Mary's Abbey catch the attention of the powerful John Thoresby, Lord Chancellor of England and Archbishop of York. One victim is a pilgrim, while the second is Thoresby's ne'er-do-well ward, both apparently poisoned by a physic supplied by Master Apothecary Nicholas Wilton. In the wake of these deaths, the archbishop dispatches one-eyed spy Owen Archer to York to find the murderer.

The Earl of Wrexford possesses a brilliant scientific mind, but boredom and pride lead him to reckless behavior. He does not suffer fools gladly. So when pompous, pious Reverend Josiah Holworthy publicly condemns him for debauchery, Wrexford unsheathes his rapier-sharp wit and strikes back. As their war of words escalates, London's most popular satirical cartoonist, A. J. Quill, skewers them both.

Salisbury, 1226. A young pregnant woman is found tangled in reeds in the river Avon, her identity a mystery. Grieving widow Ela Longespée is determined to succeed her husband as sheriff of Salisbury, and quickly takes charge of the investigation. She soon finds herself in the thick of a neighborhood scandal and a struggle to maintain her authority. With multiple suspects, can she identify the true killer?

Matthew Bartholomew, unorthodox but effective physician to Michaelhouse college in medieval Cambridge, is as worried as anyone about the pestilence that is ravaging Europe and seems to be approaching England. But he is distracted by the sudden and inexplicable death of the Master of Michaelhouse - a death the University authorities do not want investigated.

As a bard's daughter, Gwen has spent her life traveling from castle to castle and village to village with her family, following the music. In the winter of 1141, Gwen's family is contracted to provide the entertainment for the coming-of-age celebration of a lord's son. But before the celebration can begin, Gwen's father is found over the body of his friend, with a harp string as the murder weapon and blood on his hands. With the lord of the castle uninterested in finding the true killer, it is up to Gwen to clear her father's name before her father's music is silenced...forever.