Jaide and Jack Shield have a secret. When they're unexpectedly sent to live with their mysterious Grandma X, they're thrust into a world where cats talk and strange weather comes out of nowhere. There they learn that they're troubletwisters, with powers they must use to stop the Evil from taking over our world.

"There is often trouble of a mythical sort in Bath. The booksellers who police the Old World keep a careful watch there, particularly on the entity that inhabits the ancient hot spring. This time trouble comes from the discovery of a sorcerous map, leading left-handed bookseller Merlin into great danger, requiring a desperate rescue attempt from his sister, the right-handed bookseller Vivien, and art student Susan Arkshaw, who is still struggling...