Three years have passed. Uhtred has an estate in Wessex with Gisela and their two children. He receives a visit from Aethelwold, who tells him that a medium, Eilaf, has prophesied that he will replace Alfred as king of Wessex and Uhtred will become king of Mercia. Knowing that Alfred despises his brother's weakness Uhtred does not tell the king the whole story but also learns that Alfred means to marry his daughter Aethelflaed to young lord Aethelred of Mercia to provide an alliance. Another alliance is proposed when Erik returns, seeking Uhtred's cooperation in an attack on London. Instead Uhtred visits Eilaf, who tells him that one day he will be the ruler of all the kingdoms in England.

Tricked into abandoning their camp for an abortive attack on London the Saxons and Uhtred return to find it a scene of massacre with Thyra, now married to Beocca, among the few survivors and Aethelflaed captured by the Danes and taken to East Anglia as a hostage. Alfred is furious with Aethelred, to Aethelwold's delight, and sends him to negotiate her release . At the suggestion of Odda and Aethelwold, Uhtred accompanies him. However Aethelflaed finds captor Erik far more tender towards her than her brutal husband, who is richly humiliated by the Danes and she lets Uhtred know she has no desire to return to Wessex.

Uhtred returns to Alfred, keeping Aethelflaed's secret and allowing the king to believe he can ransom his daughter, setting him at odds with Odda and Aethelwold, who propose a military intervention. To his brother's annoyance Erik declares his public love for his captive but in reality he plans to keep both her and the ransom and it is Uhtred who exposes the plan, effecting his own rescue and gaining the thanks of both the princess and her father - though Alfred still does not wholly trust him.