I’ve just finished the book, which is the second part of Pullman’s Dark Materials trilogy. I am not giving any links because, if you haven’t read the thing, spoilers can really spoil it for you, as twists in the plot are always weaved in little by little, hint by hint, foreshadowing by foreshadowing.
The books are astounding in so many ways: the scope, the combination of inspiration and wit, the brilliance of descriptions, the cunning intertextual background, the restrained narrative, the way the plot flows (sometimes in a trickle, sometimes flooding through a suddenly released lock) and the subtlety of the overarching structure.
Moreover, the books work on a multitude of levels: as fantasy, as teen adventures, as metaphysical essays, and as a quite a lot in-between. I haven’t read anything like this since J. L. Borges’ short stories and (excerpts of) The Lord of the Rings.