Intro: If you love blood and guts this is for you. If you like real world historical could have beens here you go. This is a a crazy good story. The only reason I don't give this a 5 star review is that there were a few sections that seemed to linger on quite a bit.
Summary: Covers the time periods between 876 - 878: Uhtred, tires of the peace between Alfred and the Danish king Guthrum, goes off raiding into Cornwall. He comes across a settlement ruled by the British king Peredur, who hires Uhtred and his men to fight an invading Danish force led by Svein of the White Horse. Uhtred and Svein however ally to kill Peredur and pillage his settlement, and Uhtred carries off Peredur's wife, the shadow queen Iseult. A monk named Asser who was at Peredur's court witnesses the betrayal and escapes to Dyfed in Wales. Uhtred and Svein then sail up the coast to Land's End where they part ways. Svein goes to Cynuit, where Ubba was killed previously, and Uhtred to the coast of Wales where he raids a ship laden with treasure. He returns to his estate and pious wife Mildrith, using his hoard of treasure to build a great hall and relieve his debt to the church.
The Witan summons Uhtred to an audience with King Alfred in Cippanhamm, where he is accused of using the king's ship to raid the Britons with whom Wessex is at peace based on the testimony of Asser, who has made his way to Alfred's court, and wrongfully accused of attacking the Cynuit abbey on the false testimony of the warrior Steapa Snotor, who is loyal to Uhtred's enemy Odda the Younger. To settle the dispute, a fight to the death is ordered between Uhtred and Steapa. During the duel, Uhtred carries only his sword, Serpent-Breath, whereas Steapa is fully armoured. The duel is cut short when Guthrum's Danes attack and the crowd is scattered. Uhtred, Leofric, and Iseult hide in the fields until nightfall when they enter Cippanhamm and free their friend Eanflæd at the Tornake Tavern. The four of them wander for a few weeks until they reach the swamps of Athelney. As they enter the marsh, Guthrum himself attacks Uhtred. Uhtred makes a fighting escape onto a boat that carries him, Leofric, and another passenger to an island within the swamp. The passenger insists that Uhtred should have left a Danish warrior alive, and turns out to be King Alfred himself. Uthred becomes Alfred's bodyguard and for a few months they hide in the swamp until enough men have joined Alfred's army. They then fight at the Battle of Ethandun and Alfred takes back Wessex, with Uhtred being instrumental in the death of Svein of the White Horse. However, during the battle, Leofric and Iseult are both killed.