His Dark Materials: The Subtle Knife (Book 2): His Dark Materials, Book 2

In this stunning sequel to The Golden Compass, the intrepid Lyra finds herself in a shimmering, haunted otherworld, Cittagazze, where soul-eating Specters stalk the streets and wingbeats of distant angels sound against the sky. But she is not without allies: 12-year-old Will Parry, fleeing for his life after taking another's, has also stumbled into this strange new realm.