After the massacre of his Danish family, Uhtred finds himself in dangerous limbo - neither Saxon nor Dane. After approaching fearsome Viking warlord Ubba for protection, he realizes his best hope lies in the soon-to-be Saxon king, Alfred.
Uhtred and Brida flee on horseback from Bebbanburgh as Ælfric, Uhtred's uncle, and his men chase them down. By right, Bebbanburg belongs to Uhtred but he currently lacks the manpower to re-take the fortress and its lands. Using a tree branch to cover his tracks, Uhtred shakes Ælfric off in the forest. Having lost their family and their home in the previous episode, Uhtred and Brida decide to travel south to look for Ubba, warlord and friend of their deceased "father", Ragnar the Fearless. They wish to join forces with Ubba and his army to revenge Ragnar and take back Bebbanburg. They haven't journeyed too far when they encounter a small Saxon village whose inhabitants have been slain. The sole survivor attempts to shoot them with arrows before Brida hurls her axe into his back. The dying Saxon informs them that it was Danes who murdered his village, as punishment for a rebel Saxon slave who rose up and murdered his Danish master. When Brida demands the name of this alleged "rebel Saxon slave", he says it was Uhtred.
Brida is now furious with Uhtred for not controlling his quick temper. She declares it would have been better to stay under the radar, let everyone think he was dead, and reclaim Bebbanburg at a later time. Now they have a second story to contend with, one that she thinks Ubba will side with over the truth. They decide to still search out Ubba and plead their case.
In Winchester in the Kingdom of Wessex, Alfred is introduced for the first time. He is a godly man as well as a scholar, but suffers from weaknesses of the flesh, both in the form of sexual temptation as well as sickliness (what current scholars believe to be Crohn's disease). He is reminded of his duty to God's work by Father Beocca, the same priest who Uhtred grew up with in Bebbanburg. Alfred's brother, Æthelred, currently sits the throne, and the two share the same ideals of ridding England of the invasive Danes lest all of England fall to their pagan savagery. The Danes have now hostilely taken over East Anglia and captured its pious king, Edmund. Edmund calls for Wessex aid, but the witenagemot (council) decides against it, admitting that they are now the last standing kingdom of England (Eastern Mercia, East Anglia, Kent, Sussex, Essex, and Northumbria have fallen to the Danes). They must fight the pagans with Christian prayers and the blood of English men.
Uhtred and Brida arrive in East Anglia to seek out Ubba, who they know to be an unpredictable and fearsome chieftain due to his utter reliance and trust in the gods. The only way to get Ubba to hear them out is to kidnap his sorcerer, Storri, and hold him ransom. They sneak in by Uhtred pretending to be a Dane foot solider and Brida his hostage. Brida takes Storri away to the woods, with the intention of killing him if Uhtred doesn't return.
Meanwhile, Uhtred waits for Ubba's return, who enters the hall with Guthrum, another Dane warlord. King Edmund lies beaten and bloody in the middle of the church. Uhtred makes his presence known and tries to explain the truth behind the death of Earl Ragnar, much to the displeasure of Ubba. Barred in, Uhtred stands by as Ubba and Guthrum deal with King Edmund, toying with his Christian ideals by seeing if God would save him if they shot him full of arrows like Saint Sebastian. King Edmund does not survive and they turn their attention back to Uhtred. Ubba does not hear his pleas and wants to kill Uhtred, but immediately calls a halt when he learns Uhtred has kidnapped Storri. Uhtred is released in return for the sorcerer as Ubba swears to kill him one day.
Uhtred goes back to the woods where Brida hides with Storri, who is flung naked, bound, and gagged over a horse with a stick up his ass ("It was necessary", says Brida). As promised, they release him. Brida wants to go to Young Ragnar who is in Ireland. But Uhtred has come to the reality of their situation: they are no longer accepted as Danes. They will go to Wessex instead, hoping to be accepted as Saxons. Stopping in Oxford, Uhtred has a longsword made, with the amber his birth father gave to him welded into the hilt. They flee Oxford when men hired by Ubba come to kill them.
In Winchester, Æthelwold, the son of King Æthelred, is found passed out in a drunken stupor in the royal courtyard. His father is more than displeased and hints to his right-hand man, Lord Odda the Elder, that in the witan following his death, Odda must steer the line of succession towards his brother, Alfred, and not his son.
Uhtred and Brida arrive in Winchester, where Uhtred is happily reunited with Father Beocca, who takes them to see Alfred for the first time. Alfred is rather reserved in his opinions of the two newcomers, distrusting all pagans (and especially Danes) by nature. In Alfred's hall are thousands of scrolls, in which he writes down the comings and goings and happenings of all friends and enemies that his spies have managed to gather. He tells Uhtred of the importance of the written word not only for documentation but also for legacy. It is his hope that one day, all kingdoms in England will be united as one, under one god. The idea of a single kingdom called England has to begin in Wessex, the last remaining kingdom.
After Alfred goes off to prayer, Father Beocca reveals to Uhtred that he has kept the land charter papers of Bebbanburg safe and shown them to Alfred so that Alfred is aware Uhtred is the Ealdorman of Bebbanburg by right. Motivated by this, Uhtred decides to help Alfred by going into Readingham (Reading) as a spy to gain knowledge of any forseeable Danish military plans to gain his trust as an Ealdorman. He reports back to the witan that the Danes, led by Guthrum, plan to attack--and soon. The rest of the witan, Lord Odda the Younger especially, is hesitant to trust this pagan newcomer, but Æthelred and Alfred decide to follow his advice and march the Wessex army to Ashes Hill, in what follows as the Battle of Ashdown. Alfred, still mistrusting of his two guests, imprison Uhtred and Brida.