In the ninth century a Viking crew under captain Asbjörn is approaching Britain. They are fleeing from Harald Schönhaar, the king of all Northmen, who has banned them on pain of death for refusing to submit to him. Asbjörn and his men are now outlaws. They aim to plunder the rich monastery of Lindesfarne as their last chance to buy themselves out of the ban.
But their ship gets caught in a storm and sinks. Most of Asbjörn’s crew drown in the icy depths, and he and the few survivors stranded under the cliffs soon realize that this is Alba (Scotland) – the only part of Britain where there are no Viking settlements.
When Inghean, daughter of the Scottish King Dunchaid, falls by coincidence into the Vikings’ hands, they see the opportunity of an enormous ransom. So now with their hostage, the Northmen have to reach Danelag, a Viking-occupied region south of Alba. Dunchaid immediately sets his “wolfpack” on them – a group of mercenaries infamous throughout Britain and Scotland for their savagery under the cruel command of Hjorr.
The king orders them to retrieve Inghean but in no case let her reach the Danelag alive, to prevent blackmail by the Vikings. The Northmen beat their way with their hostage through the stormy highlands, the wolfpack hard on their heels. They are attacked by bandits, but saved by the plucky monk Conall. He also tells them they can never reach the Danelag by normal routes, which King Dunchaid would certainly have blocked. Their only chance is the “Serpents Path”, laid long ago by the Picts who once ruled Alba. This path leads to the coast, to a hidden grotto with boats they can use for sailing around Dunchaid’s fortifications. But the grotto entrance is flooded as soon as the winter storms begin – so the Vikings only have a few days to reach those boats.