The second book of Pullman's His Dark Materials
trilogy, The Subtle Knife marks a change in tone. Not that this is unusual
in the second book of a
trilogy, but it bears mentioning.
Lyra finds herself in the strange world of Citagazze, in which Spectres haunt the empty streets. She is soon joined by Will, a young boy from an even stranger world (ours, actually) in which humans are not accompanied by daemons. We are also introduced to Mary Malone, a scientist from Will's world with her own theories regarding the mysterious Dust that permeates all of the worlds
In particular, I was struck by the specific nature of Pullman's references to science. While most epic
fantasy adventures shy away from such specifics, Pullman demonstrates a wonderful ability to tie accurate current scientific theories into the reality of his world(s). Kudos to him for successfully tying true science fiction to the myth & fantasy realm.
As with most second books in a trilogy, Pullman advances several threads of plot and ends most inconclusively, resulting in an increased complexity of plot and structure. Additionally, he introduces further thoughtful exploration and embellishment of he themes that were hinted at in The Subtle Knife; a trait that some may consider a failing (in the tradition of tainting first installments such as The Matrix and Episodes I-III). Nevertheless, the book holds up well as an (albeit biased) account of the struggle between divine authority and human will. And just in case you were uncertain about the prevalence of this theme, it is in this book that you discover Lord Asriel's purpose: to combat and destroy the Almighty with the aid of human technology and innovation. The various other creatures met along the way take their sides--from the astonishingly feminine witches to the curiously androgynous angels--providing further comments on the nature of humanity's continuing struggle.
I would recommend this book to any YA reader who is willing to struggle with these serious religious questions. For those who aren't, The Subtle Knife is still a compelling continuation of Pullman's His Dark Materials trilogy.