Emerald Greene and the Witch Stones

There's a new pupil at St Agnes' school in the historic city of Meresbury. She's a mysterious, otherworldly girl called Emerald Greene. A girl without a past, without a family or friends. When Jess and Richie decide to befriend her, they're in for a few shocks - for Emerald lives in a mansion which doesn't exist, and can see things nobody else can see. Meanwhile, Meresbury becomes home to a series of strange events. What is the secret of the tomb which the eccentric Professor Ulverston has ...