A fragile peace is about to be broken. King Alfred's son Edward and formidable daughter, Æthelflaed, rule Wessex, Mercia and East Anglia. But all around the restless Northmen, eyeing the rich lands and wealthy churches, are mounting raids. Uhtred of Bebbanburg, the kingdoms' greatest warrior, controls northern Mercia from the strongly fortified city of Chester. But forces are rising up against him. Northmen allied to the Irish, led by the fierce warrior Ragnall Ivarson, are soon joined by the Northumbrians, and their strength could prove overwhelming. Despite the gathering threat, both Edward and Æthelflaed are reluctant to move out of the safety of their fortifications. But with Uhtred's own daughter married to Ivarson's brother, who can be trusted?