The last thing Percy wants to do on his summer holiday is blow up another school. But after doing exactly that, he is forced to flee to Camp Half Blood, where he finds that all is not well. A dangerous enemy, intent on destroying the secret training camp for young demi-gods, has found a way in through an ancient labyrinth, built by the legendary Daedalus. Percy and his friends must find Daedalus and unravel the mysteries of the maze to stop this attack, before their world is destroyed forever. But nothing is as it seems when the gods are involved . . .