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.

"The location of the glymera's notorious prison camp was lost after the raids. When a freak accident provides Nyx clues to where her sister may still be doing time, she becomes determined to find the secret subterranean labyrinth. Embarking on a journey under the earth, she learns a terrible truth--and meets a male who changes everything forever. The Jackal has been in the camp for so long he cannot recall anything of the freedom he once knew. Trapped...