Riordan, R: Percy Jackson and the Olympians: Battle of the L

In the fourth installment of the blockbuster series, the war between the Olympians and the evil Titan lord Kronos is drawing near. Even the safe haven of Camp Half Blood grows more vulnerable as Kronos' army prepares to invade its once impenetrable borders. To stop them, Percy and his demigod friends will set out on a quest through the Labyrinth.