Gwendolyn “Gwen” Chant is believed to be a powerful witch by everyone around her — but she doesn’t quite live up to her reputation. Her brother, Eric “Cat” Chant, has no magical talent at all and feels out of place.
 
They are sent to live at Chrestomanci Castle, under the care of a powerful enchanter named Chrestomanci.
 
But castle life is far from ordinary: there are secrets, magical mishaps, and strange rules. Gwen’s powers misbehave, Cat struggles with his own identity, and together they must navigate a world where magic is real — and sometimes dangerous.