When the Black Death reappears in England in 1361, Oswald de Lacy knows that the safest place for his wife and young son is the island fortress of Eden, where his eccentrically pious friend Godfrey has invited the family to stay to wait out the plague during the long, dark winter. But Oswald has barely had time to settle in when a brutal murder shocks the household and it soon becomes clear that the castle is not the stronghold of security they were desperately looking for. Oswald knows the castle isn't safe, but neither is the plague-infested countryside outside its walls. His only hope is to solve the mystery of the murder before the killer strikes again. Like something out of Chaucer, a lord and lady, a knight, a religious radical, a court jester, a drunk, and a couple of traveling craftsmen are just some of the suspects Oswald must reckon with, all under the the all-consuming threat of the plague hovering just outside the castle walls.