The date is 1373. Geoffrey Chaucer - poet, diplomat and sometime spy - is newly returned to England from a successful mission to Florence. Scarcely has he set foot on the London wharfs than he is despatched to the Devon town of Dartmouth. The Santa Giovanni, a ship from Genoa, has been wrecked and its cargo stolen, and a recent treaty with the powerful Italian city is at risk. There is tension between the mayor of the town and the Genoese shipmaster, each of whom is accusing the other of theft. Geoffrey and his assistants are lodged with Richard Storey, a wealthy doctor of physic with a fine house overlooking the estuary of the Dart. But trouble begins even before their arrival when they are ambushed en route. Once in the house they find discontent among the family, including Storey's new young wife and his moody son and high-spirited daughter. A death occurs - only that of a dog but it is the precursor to real murder. Chaucer finds himself drawn into an investigation. The household contains some intriguing visitors, among them a thrice-widowed older woman, a soft-spoken herbalist and the madam of a local brothel. Is the murderer one of them or is it a member of the band of smugglers who live in the wild woods on the shore? And what is the truth to the rumours that the Santa Giovanni was carrying a secret cargo, an object that is literally priceless?