Arriving back in Dumnonia, Merlin promptly disappears again. Meanwhile, Derfel learns that Nimue has been declared dangerously mad and has been banished to the Isle of the Dead, where the insane are exiled. Derfel assumes that this is why Merlin has disappeared. Believing Derfel and his men to be dead, Lancelot has already told Arthur and the men of Dumnonia that, despite his best efforts, Ynys Trebes fell and that it was Derfel's fault. Derfel arrives in time to hear this slander, declaring Lancelot a liar and challenging him to back up his story with his sword, but Arthur defuses the situation.