Briony knows she is a witch. She knows that she is guilty of hurting her beloved stepmother. She also knows that, now her stepmother is dead, she must look after her beautiful but complicated twin sister, Rose. Then the energetic, electric, golden-haired Eldric arrives in her home town of Swampsea, and everything that Briony thinks she knows about herself and her life is turned magically, dizzyingly, upside down.