In the second volume of the Lyonesse trilogy, The Green Pearl, King Aillas of Troicineta defends the civilian population of the Eldest Isles from the ska bandits who once enslaved him, and from the evil-doing king Casmir. Mobilizing unbridled barons in the border regions, Aillas is distracted from royal duties to capture the charming daughter of the Duke of Ska, who stung him with neglect while he languished in slavery. Finding himself alone with her, far from his armies, instead of earning the beauty's respect, he is forced to cross, in the company of a rebellious captive, the wild territory through which Casmir's mercenaries prowl. Meanwhile, fateful events occur in the world of sorcerers. The focus of the witch Desmey's hatred of the male sex was a green pearl, causing murderous greed in each of its owners; A wizard hired by Casmir kidnaps Aillas's ward Glyneth to provoke Aillas and his friends into a hopeless rescue quest on a bizarre and deadly planet in another dimension.