It is the winter of 1379 and a sea of trouble is besetting England as French privateers continue to attack the southern coast on a path to threaten London itself. In response an English flotilla of warships, with God's Bright Light in its number, has dropped anchor in the Thames. When the sun rises on the flotilla's first morning, the first mate and two of the crew of God's Bright Light have disappeared without a trace. Sir John Cranston?the wine-loving Coroner of the City?and his clerk Brother Athelstan are summoned to resolve the mysteries on board the ill-omened warship. In particular, they must search out the truth behind the death of Sir Henry Ospring, who after visiting the ship's captain was later viciously stabbed to death in a tavern chamber. As Cranston and Brother Athelstan investigate, they find themselves in the thick of a bloody battle as scandal, treason, and murder rule the day.