Betrayed by Guthred and condemned to a life of slavery, Uhtred and Halig, along with fellow slave Finan, are forced to row endlessly on a trader ship. Meanwhile, in order to gain their allegiance, Guthred welcomes Aelfric and the savage Dane brothers Erik and Sigefrid into Eoferwic,- a reward for dispatching Uhtred. But when a dispute in the terms threatens to jeopardise the agreement, Guthred offers Gisela as a peace offering. but will she comply? Having been released from imprisonment by Alfred, Ragnar and Brida are given instruction to rescue Uhtred. Accompanied by Saxon warrior Steapa, Ragnar and Hild set off in search of the slave ship. But, with the conditions at sea worsening, will they be able to find Uhtred and Halig in time? As Ragnar travels north to confront the men who sold Uhtred into slavery, he discovers that Guthred is steadily losing control of his power. Erik and Sigefrid have failed to defeat Kjartan and are still at large in the north setting up a stronghold at York once more. Meanwhile in Wessex, Alfred seeks to further his influence over Mercia by arranging a marriage for his daughter Aethelflaed.