There's an air of betrayal as those whom Odo trusts plot against him; Ecbert agrees to support Kwenthrith in Mercia; Pregnancy brings happiness to Lagertha and Kalf and a marriage is arranged.

The episode was rated 7.83 from 6304 votes.

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.

The episode was rated 7.84 from 6267 votes.

Ragnar's fleet is shipwrecked and washes up on the Wessex coast, but without enough survivors to form a credible force, Ragnar and Ivar have a difficult decision to make. Rollo meets his Viking comrades again and can't resist the urge to join Bjorn's voyage, risking his marriage and his new Frankish identity. Ragnar too is taking a risk as he carries Ivar towards the Royal Villa in Wessex – throwing himself and his son upon the mercy of King Ecbert.

The episode was rated 7.85 from 7653 votes.

Ragnar informs Floki of a heavy price he has paid for his actions; Rollo finds an unlikely ally in Count Odo; Bjorn has to fight a fierce opponent in the wilderness.

The episode was rated 7.86 from 6084 votes.

King Aelle goes to Wessex for Christmas and is not impressed with how family relations are developing; Rollo's future hangs in the balance.

The episode was rated 7.89 from 6387 votes.

Defeat for the Vikings calls Ragnar's leadership into question as they evacuate their camp and move back down river. Ragnar remains inscrutable until he orders the fleet to beach at a cliff face and unveils an ingenious plan. Rollo and Gisla have news that strengthens Rollo's position at the French Court whilst Count Odo fails to identify his true enemies, with fatal consequences.

The episode was rated 7.89 from 6721 votes.

The labors of the Vikings eventually bear fruit as, within sight of Paris, they re-launch their boats but this time along with some interesting structures that Floki has built. Aethelwulf and Alfred eventually arrive in Rome and honors are conferred by Pope Leo but relations are not so cordial in Wessex between King Ecbert and the disgruntled King Aelle.

The episode was rated 7.90 from 6843 votes.

Lagertha attempts to fulfill a long-held ambition; Ragnar negotiates an unexpected concession from King Ecbert.

The episode was rated 7.95 from 7341 votes.

Entry to Valhalla eludes Ragnar, but as he lies in his sick bed in Kattegat events unfold beyond his control. Bjorn orders the arrest of Floki for Athelstan's murder while in Paris, Rollo betrays the last of his Viking supporters to strengthen his position in the French court. In Hedeby, Kalf announces joint earldom with Lagertha, but is power sharing Kalf's true intention and is Lagertha actually willing to share what once was hers?

The episode was rated 7.96 from 6832 votes.

Bjorn's fleet sails onward and launches a surprise attack; back in Kattegat, Lagertha continues in her quest for power.

The episode was rated 8.00 from 7312 votes.

Prince Aethelwulf finds himself subject to the Vikings' battle master plan; Ecbert remains behind with a plan of his own.

The episode was rated 8.10 from 7288 votes.

Ragnar and Ivar plot against the Saxons and reach a new level of understanding.

The episode was rated 8.14 from 7674 votes.

The Viking army causes panic in the English countryside as King Ecbert and Aethelwulf plan the defense of the realm.

The episode was rated 8.20 from 7595 votes.

A ferocious battle between the Vikings and the French eventually comes down to Ragnar against Rollo. The outcome will seal the fate of the two brothers.

The episode was rated 8.21 from 7599 votes.

Ragnar's plan comes to fruition; the Viking army lands on the coast of Northumbria.

The episode was rated 8.23 from 7028 votes.