Chris Riddell & Paul Stewart 
Edge Chronicles 7: The Last of the Sky Pirates [EPUB ebook] 
First Book of Rook

Rook Barkwater lives in the network of sewer-chambers beneath Undertown, the bustling main city of the Edgeworld. He dreams of becoming a librarian knight one of those sent out to explore the mysteries of their world. Somewhere out there lie the secrets of the past including the lost floating city of Sanctaphrax and hope for a future free from the fear of tyranny. When his chance comes, Rook breaks all the rules and sets out on a journey to the Free Glades. His luck and determination lead him from one peril to another until he encounters a mysterious character the last sky pirate and is thrust into an extraordinary adventure.The Last of the Sky Pirates is the first book of the Rook Saga third trilogy in The Edge Chronicles, the internationally best-selling fantasy series, which has featured on the UK and the New York Times best-seller lists and sold more than 3 million copies. There are now 13 titles and four trilogies in the series, but each book is a stand-alone adventure, so you can read The Edge Chronicles in any order you choose.