Percy Jackson isn't expecting freshmen orientation to be any fun. But when a mysterious mortal acquaintance appears on campus, followed by demon cheerleaders, things quickly move from bad to worse.
 
In this forth installment of the blockbuster series, time is running out as war between the Olympians and the evil Titan lord Kronos draws near. Even the safe haven of camp Half-blood grows more vulnerable by the minute as Kronos's army prepares to invade its once impenetrable borders. To stop the invasion, Percy and his demigod friends must set out on a witch stunning surprise at every turn.