After the first part of the trilogy, it made no sense to me that parts two and three had not been adapted to film, as well.
Yet, now after (re)reading part two, I can clearly see why those never hit the screens : There is no way in hell any American major film company would ever have agreed to put out a film for youngsters displaying such an exceedingly evil mother - Kidman's character was sugar-coated in 'The Golden Compass' - and Pullman's criticism of the church (and God!) goes from scathing (in the first book) to downright murderous.
I enjoyed this, though, and so did my offspring.
It is a bit long-winded (Why do so many writers tend to fall in love with their characters?) but thought-provoking and inventive.
Rowling had clearly read this before having a go at her first writing project..!