In Eaters of the Dead, Michael Crichton weaves a retelling of the Beowulf epic with a marginally factual ancient manuscript about an Arab who travelled North. Ibn Fadlan and his manuscript are purported to be true but their influence on Crichton's book is minimal. Once the Ibn Fadlan Manuscript has been exhausted, Crichton carries on the tale in the same tone and style of Ibn Fadlan. The effect is both interesting and slightly frustrating to the reader. For those scholars interested in Beowulf, Crichton's version varies too much from the original and can cause consternation. At the same time, the reader can appreciate that Crichton has put forth a book that is at once believable fact and false fiction.

Ibn Fadlan is charged by the Caliph of Bagdad to travel on a mission to the North country. On his journey, Ibn Fadlan is sidetracked by a group of Vikings who insist he accompany them on a journey of their own. They say it is part of their tradition that a foreigner must join them in this excursion, helping them form a band of thirteen men. Ibn Fadlan tries to protest but there is no way he can extricate himself from the mission. Ibn Fadlan travels deeper into the Northern countries and is both fascinated and appalled by what he finds there. Ibn Fadlan tries desperately to cling to the tenants of his Muslim faith but the Vikings do not take kindly to his prayers or mentions of Allah. Ibn Fadlan is constantly repulsed by the mannerisms of the Viking people but also finds there are several similarities between his culture and theirs.

Buliwyf is the leader of the thirteen men who travel across the sea to the kingdom of Rothgar. Buliwyf stands to be made king in his own territory should he return successful and this is why he undertakes this journey. A messenger reveals that a terrible monster known as the wendol has been attacking Rothgar's hall. Rothgar is an old man with an aging constituency and so is unable to mount a suitable war party against the wendol. Buliwyf agrees to take on the task even though a premonition suggests he will not survive the encounter.

The wendol are hairy creatures that come out of the mist to attack suddenly. They possess humanlike qualities and yet are not completely human. They are lead by an aging female who surrounds herself with snakes and lives deep in the thunder caves near the sea. When attempts by Buliwyf and his men fail to vanquish the wendol on land, a dwarf tells the men they will have to seek out the female in the thunder caves. Only when the mother has been slain will the wendol become less of a threat and easier to overcome.

Ibn Fadlan is expected to fight alongside the Viking warriors even though he is inexperienced in battle. He quickly becomes lost in their battle frenzy and even finds himself ravishing slave women prior to battle in the same manner the Viking warriors do. Ibn Fadlan maintains his Muslim faith but also adopts many Viking ways. His willingness to participate in their adventure earns him an honored place among the company and in Rothgar's hall. Ibn Fadlan is even one of the warriors chosen to prepare Buliwyf's body for burial and to engage in the ceremonial slaying of a young woman who will be burnt alongside Buliwyf's body.

Despite his new found capabilities and his friendship with several of Buliwyf's warriors, Ibn Fadlan begs leave to return to his own country and conclude his original mission for the Caliph. Ibn Fadlan is finally given permission to return South and he never sees the Viking warriors again. When he departs the Viking camp he promises to write about their epic battle and Buliwyf's heroism. The Ibn Fadlan Manuscript is supposed to contain this story.