Arthur takes Gundleus prisoner. Nimue struggles with the trauma of her rape and plans to kill Gundleus. Arthur learns that Gundleus' uncle Gorfydd is preparing for war. Nimue tries to pull Derfel into her plans, but Derfel can't betray Arthur.
Arthur believes that Bedwin will be able to negotiate peace with Gorfydd; however, when Morgan and Derfel arrive in Powys, they discover a horrific site.