Poet and diplomat Geoffrey Chaucer, newly returned from a delicate mission to Florence on behalf of Edward III, is despatched to sort out a home-grown problem in the Devon seaport of Dartmouth. Geoffrey must leave his family in London and travel west, expecting to solve the theft of the cargo of a Genoese ship with comparative ease. Chaucer and his companions are lodging with a wealthy doctor of physic in his fine house overlooking the water. But there is deep hostility in the port town between citizens and sailors — accusations and daggers fly.

There are tensions in the house as well, and murder occurs soon after their arrival when one of the occupants is done to death in the herb garden. Geoffrey investigates the death and its possible connection to the theft. Meanwhile, Philippa Chaucer, staying in the Palace of Savoy, is warned of a conspiracy against Katherine — her sister and the mistress to John of Gaunt, now the most powerful man in England after the king. Philippa once saved Katherine's life during an outbreak of plague when they were children. Will she again be called on to protect her sister from her equally dangerous enemies at court?