[4x11 - The Outsider]Ragnar has returned to Kattegat and there are secrets to be revealed. He makes plans to return to Wessex to right past wrongs but finds that those who were once his closest allies now have plans of their own. Even the Lothbrok sons refuse to join their father’s mission – except one.
[4x12]The Kattegat locals chide Ragnar that the gods have deserted him as he struggles to crew his voyage to Wessex. It’s Bjorn who has charisma now as he prepares to fulfill his long-held dream to explore the Mediterranean in a sleek new boat built for him by Floki. By contrast, Ragnar must accept weathered boats and a crew he has bribed but when Aslaug foresees that the fleet will be lost in a vicious storm her warnings go un-heeded by Ragnar and her precious son, Ivar.
[4x13]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.
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They weren't even trying to be *mysterious*, the episode summaries give away a lot, so if you don't want spoilers, don't read them.