The Dukedom of Caprona is a place where music is enchantment and spells are as slippery as spaghetti. The magical business is run by two great spell-houses - one owned by the Montana family, the other by the Petrocchis - and they are deadly rivals. So when all the spells starts going wrong, they naturally blame each other.

Chrestomanci suspects an evil enchanter; others say it is a White Devil. Or maybe a different kind of magic is needed to save Caprona...