Bartimaeus Trilogy, Book Three: Ptolemy's Gate

In this thrilling conclusion of the Bartimaeus trilogy, the destinies of Bartimaeus, Nathaniel, and Kitty are thrown together once more. For the first time, the secrets of Bartimaeus's past are revealed, and the threesome must face treacherous magicians, unravel a masterfully complex conspiracy, and defeat a formidable faction of demons.