In The Subtle Knife, a young boy named Will meets Lyra in a haunted world filled with ghostly monsters called Spectors. Will and Lyra are both from Oxford. Lyra's Oxford contains people's souls walking beside them as talking animals otherwise known as "daemons." To follow that, Lyra's world is also filled with Spectors alongside powerful and beautiful witches. Will's world contains the same familiar objects and creatures as ours.
Will takes Lyra into his world, where a dishonest man steals Lyra's compass and then tells them to bring him a knife if they ever want it back. But when they go to find the knife, turns out that it really belongs to Will, after he loses two fingers fighting for it. But the thing that irks me about it, is that the man who wants it doesn't know how to use it. And therefore, he was stupid to ask for it because all he really wants is to travel to other worlds, and the knife does allow you to do it but he knew it wasn't going to work if the holder didn't work it properly.
One thing I noticed about this book is that Lyra (even though she's the child, who's a very important person in the first book) is much less important than Will, who is, surprisingly, a new character. And that Lyra starts using the alithiometer less and less, Pan is now referred to as "Pantailomon," who was mentioned a fair amount of times in the book before "The Golden Compass", but now his name is barely mentioned at all, and so is Mrs. Coulter's daemon, who was mentioned a surprisingly high amount before.
The setting where Lyra and Will meet each other is the haunted world, which is a good place to meet. It adds a little twinge of fear when you hear that Lyra and Will have been standing right in the middle of conscience-sucking ghosts the whole time they were there.
Notice how most of the characters don't feel a lot of fear when a big battle comes. Lee Scoresby for instance. Whenever he gets in a big mess he's always calm and sophisticated.
I recommend this book to people who love suspense and action. And for curious people like me. After all, Lyra does find out a lot about Dust in this book.