The second adventure in the Bartimaeus trilogy finds our young apprentice magician Nathaniel working his way up the ranks of the government, when crisis hits. A seemingly invulnerable clay golem is making random attacks on London. Nathaniel and the all-powerful, totally irreverent djinni, Bartimaeus, must travel to Prague to discover the source of the golem's power. In the ensuing chaos, readers will chase a dancing skeleton across London's skyline, encounter the horror of the dreaded Night Police, witness a daring kidnapping, and enter the Machiavellian world of the magician's government. Eventually, Nathaniel and Bartimaeus have to go head to head with the fearsome golem before the surprise identity of his master is finally revealed.

In their continuing adventures, magician's apprentice Nathaniel, now fourteen years old, and the djinni Bartimaeus travel to Prague to locate the source of a golem's power before it destroys London.