The Powder of Death opens with a returned envoy to China meeting an English scholar in Oxford, in the mid-13th century; their purpose is to share a deadly secret. They vow that the knowledge of gunpowder must die with them. The novel tells the story of its re-discovery, one man's obsession with the powder of death, and Edward III's determination to use it to his advantage. The nature of warfare is changed forever, and the world hears the death-knell of Knightly chivalry.