The first part of this book is set in the city of Oxford, while the second and last parts of it are set in the far North of the planet. However, this Oxford is on an alternative earth, with humans whose souls are "familiars" in the form or animals that live outside the bodies of their human counterparts. Each individual's daemon is closely linked to his or her human and symbolizes something about their human's character.

At the same time, humans carry on verbal and mental conversations, even arguments, with their daemons, which are usually of the opposite sex. A daemon continues to change from one animal to another until the humans pass through puberty. At this point in a person's life, the daemon becomes fixed.

When the person dies, it seems to disappear.

The work follows the perspective of Lyra, first describing her unlikely home in an...