Camp Half-Blood is no longer safe. The barrier protecting the camp is failing, monsters are breaking through... and no one knows why. A year after Luke Castellan’s betrayal, everything seems to be getting worse. Percy, Annabeth, and you are sent on a quest to find an ancient artifact capable of saving the camp. But as you journey onward, a truth begins to come to light: Luke didn’t disappear... he is closer than you think. And this time, the line between enemy and ally isn’t quite so clear.