Sir Mordred's triumphant return after laying siege to the Vikings is bittersweet for our heroes. While they are awestruck to see the king's champion and dear friend in person, they are saddened by the knowledge that this latest battle with the Vikings could have been avoided. Valiant, Arn, and Rowanne are more determined than ever to discover the identity of the traitor within Camelot's walls. This search for the truth brings the prince to the attention of two powerful new enemies who need him silenced to further their own agendas.