The intrepid young Lyra has passed through a shimmering portal in the sky nd finds herself in a beautiful, haunted otherworld - Cittàgazze, where soul-eating Specters stalk the streets and wingbeats of distant angels sound against the sky. But she is not without allies: twelve-year-old Will Parry, fleeing for his life after taking another's, has also stumbled into this strange new realm.

On a perilous journey from world to world, Lyra and Will uncover a deadly secret: an object of extraordinary and devastating power. With every step, they move closer to an ever greater threat - and the shattering truth of their own destiny.