This book sets a much darker tone to the series and adds more meaning to the characters' actions in Northern Lights.
It also begins to explain about Lord Asriel's rebellion against the Authority and the church. This book also deals a lot with the matter of Dust or dark matter. During this book, Lyra starts getting a bit less selfish and begins to realise some of the true intricacies of the alethiometer. It follows on from Northern Lights (also known as The Golden Compass) by adding a new protagonist Will Parry, who, around the same time as Lyra Silvertongue discovers a window to gain access to Cittàgazze, a world haunted by Spectres and a city inhabited entirely by children.
The Subtle Knife is the second book in the His Dark Materials trilogy. Lyra Silvertongue: ' What is he? A friend or an enemy?' Alethiometer: ' He is a murderer.' - Blurb quote
