In the 22nd century, Sophie and her father visit the carefully preserved region of Urstwile, where witches and devils still roam. In Sophie's technologically advanced world, travel and communication are almost instantaneous, but developments in psychology have made love obsolete. Thoroughly trained in levitation and hypnosis, she can't resist assisting the inhabitants of Urstwile; after she has freed the somber Prudence from the spell of the feared witch, Dorcas, and painlessly extracted an infected tooth from a pugnacious blacksmith, the townspeople assume she's a witch and try to lynch her. But the mob catches Prudence instead of Sophie, to the dismay of Prudence's rescuer, Simon, who's in love with Sophie. After romping about in a forest of peripatetic trees infested with fiends who are malign but ""lack application,"" everyone takes refuge in Dorcas' hovel, where Prudence's love for Simon proves the most powerful force around. This lighthearted satire is crammed with witty detail--a ""slightly superior fiend"" who muffs his assignment because he's trapped in a cricket's body; Sophie's scientist Dad, doing his research by hearsay. Lillington is a less disciplined writer than Diana Wynne Jones, that master of satirical fantasy, but his unbridled imagination and good humor have provided a fine comic story.