Ragnar and his crew sail out with Earl Haraldson's permission.

Ragnar, weak and still hurt, must meet the Earl head-on after it comes to light that Rollo has been tortured on Haraldson’s orders. The two men will come together face to face with a single outcome possible: Only one man will leave this fight alive.

Three Viking ships sail toward the Royal Villa of King Aelle in eastern England. Ragnar wants ransom in exchange for peace, but the king has a very different plan in mind.

Ragnar and King Horik clash over how to dispense justice to Jarl Borg. In Wessex, King Aelle arrives and Ecbert has an eye on a new alliance.

Ragnar's warriors march on to King Ecbert's villa and are met with a surprisingly vicious welcome party.

There is bitterness in the camp, Floki is angry over the alliance with Ecbert.

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

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 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.

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

The Viking army begins to gather in Kattegat. Lagertha must remain vigilant in the absence of her son, Bjorn.

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