1361. Plague has returned to England-thirteen years after the devastation of The Black Death. As destruction advances towards his estate in Kent, Oswald de Lacy leads his family to the safety of a remote castle in the marshes-where his friend Godfrey is preparing a fortress to survive the coming disaster. The rules are clear: once the de Lacys and the other guest are inside the castle the portcullis will be lowered and no one permitted to enter or leave until the Pestilence has past. And then murder strikes. Oswald is confronted with a stark choice-leave and face the ravages of the plague. or stay and place his family at the mercy of a brutal killer. With word of his skills as an investigator preceding him, it falls to Oswald to unmask the murderer in their midst. Host, guest, or servant-everyone is a suspect in this poisoned refuge of secrets, deceit, and malice.