Bartimaeus Trilogy

from wikipedia

- The Amulet of Samarkand 
- The Golem's Eye 
- Ptolemy's Gate

As the books progress, three cycles become evident. The first and largest from the overarching plot line standpoint is the rise and fall of London as a world power. The second and third are more personal; the boy changing from the pitiful, yet noble, Nathaniel, to the power hungry, arrogant John Mandrake and back again to the boy he was, and the third, involving Kitty and Bartimaeus, who have one of the most unusual relationships ever between human and spirit, who restore each other’s faith in their races.

The Amulet of Samarkand The first book in the series introduces Nathaniel as the gifted 12-year old apprentice of a middle-aged mid-level magician, taking his first lessons in the arts of magic. When the magician Simon Lovelace cruelly humiliates Nathaniel in public, Nathaniel decides to have his revenge by stealing a powerful amulet from Lovelace. Unknown to his tutor, he begins the study of advanced magical incantations in order to summon the djinni Bartimaeus and enslave him. But Bartimaeus overhears Nathaniel’s birthname, which greatly reduces Nathaniel’s hold over him (since he can cast counterspells incorporating the birthname). Things soon get out of hand and Bartimeaus and Nathaniel find themselves caught in the middle of magical espionage, murder, blackmail, and revolt.

The Golem’s Eye The second book picks up almost three years later and features Nathaniel as a junior magician working his way up the government ranks. In this book Kitty Jones is introduced as an important character. She is a part of the resistance movement which seeks to end the oppressive rule of the magicians. Nathaniel is tasked by his superiors to crush the resistance movement and capture the members. His task is complicated when a seemingly invulnerable clay golem starts to make random attacks on London. Much to the displeasure of Bartimaeus, Nathaniel recalls the djinni to aid him in uncovering the origins of the golem.

Ptolemy’s Gate In the final book of the series, Nathaniel is a senior magician and a member of the ruling council, an elite class of magicians in the government. Bartimaeus is still trapped on Earth by Nathaniel and is treated with disdain. Meanwhile, Kitty Jones has been hiding undercover and completing her research on magic and spirits. She hopes that this will enable her to break the endless cycles of conflicts between djinn and humans. The main plot of this story is a conspiracy to overthrow the government which causes the most dangerous threat in the history of magic. Together, Nathaniel, Bartimaeus and Kitty try to save the city of London from this dangerous threat.

Bartimaeus tells us that there is a never-ending cycle going on, where magicians take over commoners, the magicians summon spirits, the spirits spread magic throughout the city, some of the commoners gain a resistance to magic, the commoners rebel against the magicians, the magicians are overthrown, and the spirits go back to the Other Place until once again another magical empire rises up. This cycle proves to be the main plot, with the overthrowing of London. Bartimaeus makes references to other magical empires in his long life, such as Baghdad and Egypt, all of which have fallen from power as well.