Book I of The Jorvik Trilogy tells the story of Halfdan Ragnarsson, a son of Ragnar Hairy-Breeches, and brother to Ivar the Boneless and Ubba, Bane of the Frisians. Halfdan arrives in England as joint commander of the Great Heathen Army seeking revenge for the killing of their father. The army carves a brutal campaign through the Anglo-Saxon kingdoms, capturing Eoforwic and renaming it Jorvik. But as the blood of kings and warriors spills, Halfdan must learn that conquest is only the beginning and that power comes at a price even a Viking might fear to pay.