Throughout the worlds, the forces of both heaven and hell are mustering to take part in Lord Asriel's audacious rebellion. Each player in this epic drama has a role to play—and a sacrifice to make. Witches, angels, spies, assassins, tempters, and pretenders, no one will remain unscathed.

Lyra and Will have the most dangerous task of all. They must journey to a gray-lit world where no living soul has ever gone and from which there is no escape.

As war rages and Dust drains from the sky, the fate of the living—and the dead—comes to depend on Lyra and Will. On the choices they make in love, and for love, forevermore.