Uhtred the fearless and instinctive warrior, begins his voyage north to avenge Earl Ragnar's passing and recapture his ancestral lands of Bebbanburg from his traitorous uncle, Aelfric. King Alfred's conviction to unite the separate kingdoms of England is stronger than ever and he sets his sights on the wild lands of the north, which have fallen into the control of savage Dane brothers Sigefrid and Erik. Upon receiving word from Brother Trew and Father Beocca about a prophesised new king in the form of Christian Dane Guthred, Alfred sends the priests on a rescue mission, weighted in silver to free Guthred from the hands of slave traders. Elsewhere, Uhtred still feels the loss of Iseult and, fearful that they are straying from their journey north, Hild takes matters into her own hands to advance their quest. While crossing paths with Father Beocca in Eoferwic, Uhtred finds himself embroiled in a rescue mission and is brought face to face with an enemy of old. As the team enter into dangerous territory, will the exchange of ransom go to plan?

When spies infiltrate the Cumbraland army, Uhtred must rely on his troops to protect him from a perilous attack. Spurred on by the recent rogue ambush, Guthred makes a decision to march on Eoferwic. However, Abbot Eadred's disapproval of Uhtred grows to dangerous heights and his influence over the Dane King threatens the alliance between Guthred and Uhtred. Finding himself face to face with ruthless brothers Erik and Sigefrid, will Guthred's efforts to emulate Alfred's conciliatory tactics backfire? Meanwhile, Hild goes on a journey of self-discovery as she considers exchanging her life as a nun for that of a warrior. Seeking to prove herself to Uhtred's men, she sets about a gruesome task. Elsewhere, Kjartan's thirst for revenge grows stronger, as Uhtred rides as the dead horseman once again. When affection between Uhtred and Gisela reaches new heights, Uhtred's enemies close in and he suffers a grave betrayal.

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.

Guthred's lack of judgement has divided Northumbria. Having sworn his allegiance to Alfred once again, Uhtred must travel North to defeat the brothers Erik and Sigefrid, take back Eoferwic and reassert Guthred's authority. Alfred spots an opportunity to remind Guthred of his duty to Wessex and sends Aethelwold to join Uhred's riding party. But with the responsibility of ensuring Eoferwic's future as a Christian region thrust upon him, Aethelwold's judgement becomes clouded. Joining Brida and Ragnar's men in Loidis, Uhtred and the others discuss a plan of attack and turn their attention to Dunholm. Ragnar is intent on avenging Kjartan: can Uhtred come to his aid without defying Alfred? Meanwhile, a confrontation with the Northmen brings a shocking turn of events and elsewhere, hostility is rife when Sven attempts to reason with Thyra. But will she want to hear what her captive has to say?.

Some time has passed since the battle of Dunholm and Uhtred still serves Alfred as lord of the Wessex town of Coccham. Despite the peace of recent years, trouble is brewing in nearby East Anglia and Aethelwold brings Uhtred a strange tale along with a proposition that is hard to ignore. Uhtred's continued strong will and latent restlessness creates tension and strain during a royal visit from Alfred and an unexpected meeting with the Northman Erik gives Uhtred more food for thought, although it puts he and Gisela at odds. Meanwhile, at Winchester, preparations for the royal wedding are underway as Aethelred of Mercia arrives. Beocca confides in Uhtred and is left with an important question to ask.

Winchester celebrates Aethelred and Aethelflaed's wedding, but the festivities are short-lived as the clouds of war gather and Alfred runs out of options to keep the peace. When rumours swirl, Alfred's mistrust of Uhtred reaches a new low and Uhtred is relegated in his duties as the warlord of Wessex. Aethelred is called to step up to the plate, but a fatal mistake allows Erik and Sigefrid to outwit the Saxons and terror reigns.

Driven to hiding in the marshes after the Vikings invade Wessex, Uhtred and Alfred finally make amends and devise a plan for retaking the kingdom.

Calling upon Saxon forces to rally and drive the Vikings out of Wessex, Uhtred and Alfred prepare for a decisive battle, but treachery awaits.