After being warned by a fortune-teller that their fight against legendary creatures is doomed to failure unless they have a 13th warrior, a travelling ambassador (Banderas) is given no choice but to join a group of fierce fighters.

Book summary: In A. D. 922 a refined Arab courtier, representative of the powerful Caliph of Bagdad, encounters a party of viking warriors on their journey to the barbaric North. He is appalled by Viking customs. But only in the depths of the Norhtland does he learn the horrifying truth: He has been enlisted to combat a terror that comes under cover of night to slaughter the Vikings and devour their flesh.... Movie summary: After being warned by...