Mandy Lamb is the world's only half-sheep girl, thanks to a spot of well-meant but ill-advised genetic tinkering. She's grown up happily in the Valley of Worth with friends both ovine, human, and one who is neither.
But now she's off to senior school in the nearby town. And she's about to meet James, a rather strange orphan who smells, to Mandy, distinctly like a dog, and who has a bad habit of running away at the full moon. Is there any way they can be friends?