Chris, the mischievous hero of this sparkling fantasy, finds an odd stone when he steals a ride in his friend's grandmother's wheelchair, and he soon comes to realize that the stone is magic, the old lady is a witch, and the Fine Thread Association to which she belongs is a network of sorcerers who send crocheted messages by bird. A sinister bunch they seem to Chris when they learn of his find and attempt, separately and together, to retrieve the stone. But the grandmother becomes less scary and, deciding that Chris' responsible and reluctant use of the magic stone qualifies him as her successor, she whisks him off to the forest. . . and into the clutches of another old woman named Janna. In the end Janna proves less wicked than frail, as do the association members who track the stone to her forest hideout; but the issues raised by the adventure are not resolved and in fact the story, which loses momentum with the shift of scene, seems to peter out in the direction of a sequel. Nevertheless Kooiker's view of the stone's special power is refreshingly sound; Chris is an engaging protagonist; and his early experiences with the stone (inadvertently turning one teacher into a monkey and another, grim one into a cavorting child) are lively and attractive enough to keep readers ensnared to the end. . . and into a sequel.