When demonic cheerleaders invade his high school, Percy Jackson hurries to Camp Half Blood, from whence he and his demigod friends set out on a quest through the Labyrinth, while the war between the Olympians and the evil Titan lord Kronos draws near. Sequel to "Titan's curse" (EB74453). Some descriptions of violence. Grades 5-8. 2008. (Percy Jackson & the Olympians ; 4)