The Subtle Knife (His Dark Materials Series #2)

The Subtle Knife (His Dark Materials Series #2) - This book is the second of the trilogy. It starts of in a parallel world (our world) and moves on to different worlds from there. This book is really fast and interesting but since it's the middle of the story it's more a build up towards the last book so even though many things happen, the events important to the plot still haven't been solved. If you liked the first book then you HAVE to read this one and the Amber Spyglass!