Still trapped in the gawky mortal body of Lester Papadopoulos, the former sun god Apollo follows a riddling prophecy westward to Indianapolis, hunting a long-forgotten Oracle hidden in a cave "blue and hollow." He travels aboard a bronze fire-breathing dragon with the mechanic Leo Valdez and the once-immortal sorceress Calypso, now adjusting painfully to mortal life, while his demigod master Meg McCaffrey wrestles with loyalties pulled in two directions. In the city they find refuge at the Waystation, a sanctuary run by two former Hunters of Artemis whose adopted daughter has gone missing after seeking a dangerous prophecy. Standing against them is a second member of the ancient Triumvirate, a bloodthirsty Roman emperor who craves spectacle and adoration and whose vanity rivals even Apollo's former pride. The quest forces the diminished god to confront the Oracle of Trophonius, a source of guidance so harrowing it can shatter a mind. Apollo's narration keeps its trademark wit and self-mocking haiku, but grief and tenderness seep in as he learns the cost of the favors he once granted and the people who paid it. Friendship, sacrifice, and the slow work of becoming worthy carry the story as the companions risk everything to free captives, rescue the missing girl, and wrest another silent Oracle from imperial control. By the end, the god who once stood above all mortals understands a little more of what it means to love and to lose.