The second-to-last book in fantasy series are often long setups for the finale, but this thrilling maze quest tale stands well on its own and even offers exciting new characters to follow. The idea of a labyrinth growing on its own under the United States fascinates, and it means Percy and friends can pop in on New York City, the West Coast, and the Rockies without so much surface travel by wild boar or monster cruise ship or Pegasus. They just have to get through a ranch full of flesh-eating horses, a monster-fighting arena, and the demon-infested hot-lava center of Mount St. Helens -- no problem -- and see what part of the country they end up in next. Readers learn more about the inventor of the labyrinth, Daedalus, and his tragic tale. Fascinating layers are added as The Battle of the Labyrinth moves along. Daedalus drives not just the twists and turns of the maze, but of the twists of the story as well.
Daedalus isn't the only tragic, complex character to have an impact, however. Nico, son of Hades, grieving his sister lost in Book 3, and holding a serious grudge against Percy, plays a role in making the quest more difficult. Still, Percy won't give up on helping Nico, no matter how stubborn he is. In this way Percy is perceptive, patient, and astute. When it comes to girls, however, he's rather clueless. Poor Calypso, poor Annabeth. Maybe by the finale, sometime before the Titans' world-ending battle, Percy will navigate this dangerous maze of feelings a bit better.