A Good Treason
Entry to Valhalla eludes Ragnar but as he lies near death in Kattegat, events unfold beyond his control. Meanwhile, Kalf announces joint Earldom with Lagertha, but is power-sharing Kalf's true intention?
Kill The Queen
As Ragnar and Floki remain at odds, Rollo makes great efforts in Paris to win over his new bride, Princess Gisla. Meanwhile, King Ecbert sets the task for his son Aethelwulf to rescue Queen Kwenthrith.
Ragnar sees that Floki faces devastating punishment for the murder of Athelstan, but as Floki remains a prisoner, a mysterious visitor to Ragnar counsels mercy. Rollo finds an unlikely ally in Count Odo.
A Norwegian King and Bjorn visits Kattegat. King Aelle visits Wessex for Christmas and is not impressed with how family relations are developing. While in Paris, Rollo's future hangs in the balance.
Those whom Odo trusts plot against him and Ecbert agrees to support Kwenthrith in Mercia. Pregnancy brings happiness to Lagertha and Kalf and a marriage is arranged but events take an unexpected turn.
What Might Have Been
Ragnar announces another raid on Paris at the Thing in Kattegat and although the fleet is battered by a storm after it sets-out, the greatest challenge for them lies ahead in Paris, where Rollo awaits.
The Profit and the Loss
In England, King Ecbert's ambitions are revealed as he schemes to gain the crown of Mercia while outside Paris, the Vikings attack with considerable force but can they breach Rollo's defenses?
Defeat for the Vikings calls Ragnar's leadership into question as they evacuate their camp and move back down-river. Ragnar himself remains inscrutable and unveils an ingenious plan.
Death All 'Round
The labors of the Vikings eventually bear fruit as they re-launch their boats but this time along with some interesting structures that Floki has made. Aethelwulf and Alfred eventually arrive in Rome.
The Last Ship
A ferocious battle between the Vikings and the French eventually comes down to Ragnar against Rollo and the outcome seals the fates of the two brothers.
Ragnar has returned to Kattegat & there are secrets to be revealed. He makes plans to return to Wessex to right past wrongs but finds those who were once his closest allies now have plans of their own.
The Kattegat locals chide Ragnar that the gods have deserted him as he struggles to crew his voyage to Wessex. Bjorn prepares to fulfill his dream of exploring the Mediterranean.
Ragnar and Ivar face a difficult decision in regard to their crew after their fleet is shipwrecked and washes up on the Wessex coast. Bjorn has an unexpected reunion.
In The Uncertain Hour Before The Morning
Lagertha fulfills her long-held ambition to take Kattegat but will she spare Aslaug? King Ecbert must also decide if he can spare Ragnar, his friend, or hand him over to King Aelle.
All His Angels
King Aelle can't hide his pleasure when he sees Ragnar arriving into his territory in a cage. But Ragnar has laid his plans well and Aelle is unaware of what he is about to unleash.
Back in Kattegat, Lagertha consolidates her position as the new Queen, despite Ivar's threats. But the sons of Ragnar will soon be distracted when a stranger brings word of the fate of Ragnar.
The Great Army
The sons of Ragnar declare war on England & a great army begins to gather in Kattegat. But Lagertha must be vigilant in her new role as Queen, only the return of her son Bjorn can assure Lagertha's safety.
King Aelle feels confident that he can deal with any incursion from the Northmen. But the scale of the Viking force he faces & the fate he suffers at their hands is beyond anything he could have imagined.
On The Eve
The Great Heathen army causes panic in the English Countryside as King Ecbert & Aethelwulf plan the defense of the realm. Lagertha must plan her defense & deal with the threat from King Harald Finehair.
Prince Aethelwulf finds himself subject to Ivar's battle masterplan. But as the Royal Villa is abandoned in the face of the approaching Viking army, Ecbert remains behind with a plan of his own.