Arab courtier Ahmad Ibn Fadlan is sent to the barbaric north as an emissary, because he fell in love with the wrong woman. In AD 922, this usually meant goodbye forever. Shortly after the party ran into exploring Vikings and befriended them, a young boy reaches the camp to call the warriors home: The Wendol, creatures of the Mist, have started attacking their homeland, killing and eating everyone in their way. The oracle forces a thirteenth warrior to accompany the Vikings, but this must not be a man from the north. Ahmad Ibn Fadlan, who quickly is nicknamed Eban, first does not feel comfortable with the strange men of the north, but when he finds out that the Wendol really exist, he bravely fights alongside the Vikings in a battle that can't be won.