In the kingdom of Springfieldia, the Serfsons visit Jacqueline Bouvier at The Webs at Giant Spider Acres, a retirement forest, of which Marge discovers, to her shock, that Jacqueline is freezing over.
At Barber Hibbert's Surgery, Jacqueline is found with progressive frozen mortification after having being bitten by an ice walker, which converts the victim's flesh to ice in the span of a week. To save her, he proposes a treatment, buying an Amulet of Warmfyre. However the cost for it is too high, and Marge sends Homer to grab the necessary money. Azzlan appears trying to get the Serfsons to convert to Christianity only to be driven away by Marge.
At the Springfieldia Nuclear Power Plant, Homer attempts, unsuccessfully, to ask Lord Montgomery for the money. Seeing her father's plight, Lisa solves the problem by magically converting lead into gold. However, Lisa cannot perform magic in public as then she would be taken by King Quimby and get forced to become one of his evil wizards.
At home, Marge gives the amulet to Jacqueline, who refuses at first, recognizing the futility of life, though she decides to wear it. At that moment, King Quimby's wizards appear and take Lisa away, charging her with witchcraft. To rescue her, Homer rallies the town's peasants into revolt. Upon scaling the castle, the peasants defeat King Quimby's wizards only to face a dragon. Jacqueline decides to remove the amulet, turning her into an ice-compository human and sacrifice herself to defeat the dragon of which she succeeds. However, it is revealed that the dragon was the source of all magic in the kingdom including all magical creatures. Lisa suggests that the kingdom can now base their lives on science, to everyone's dismay. Homer decides to light coals in an attempt to revive the dragon. This succeeds only for the dragon to burn the village down.