exactly what the title says.

In the final battle between Percy and Kronos, Annabeth betrays Percy and all of Olympus. Kronos rises. Luke survives. The gods are imprisoned. Percy is sent to Ogygia before he is killed. Now, a year later, Percy is back to settle the score. And he's mad.

Saint Dane is the Demon Traveler now - but was it always so? Before the beast, there was a hero. Press Tilton's adopted daughter Chase, now an orphan once more, is about to learn that there are things worse than the death of a father: the betrayal of one.