The Lives of Christopher Chant

Young Christopher Chant, in training to become the next Chrestomanci or head controller of magic in the world, becomes a key figure in a battle with renegade sorcerers because he has nine lives. After Christopher discovers that his dreams are so realistic that he can actually visit other worlds and bring things back from them, he must decide whether his beloved uncle's encouragement of these expeditions is altruistic or part of a frightening illegal scheme.