The battle starts, literally, with an explosion and doesn't let up. After Percy destroys the high school band room battling monsters called empousai who have taken on the form of cheerleaders, he has to hide out at Camp Half-Blood. There, Grover's searcher's license is going to be revoked unless he can find the god Pan in seven days. An entrance to the Labyrinth has been discovered, which means that Luke, the half-blood turned bad, can bypass the magical protections and invade the camp. Annabeth insists that she must follow a quest to locate Daedalus's workshop before Luke does. Percy is disturbed by visions of Nico, the son of Hades, who is summoning forth the spirits of the dead with McDonalds Happy Meals. Percy, Grover, and Percy's Cyclops half-brother follow Annabeth into the maze not knowing if they will ever find their way out.