Jason awakens on a bus in the middle of the Arizona Desert, surrounded by kids his own age and being bossed around by a coach. He has no idea who he is, nor who the people around him are. They are soon attacked by storm spirits, and Jason instinctively knows what they are and how to fight them. He and two other students- Piper, who says she's his girlfriend, and Leo, who says he's his best friend- are rescued by Annabeth & Butch (a new demigod), and are flown to Camp Half-Blood. By order of Zeus, Mt. Olympus has cut off communication with all mortals, including Camp Half-Blood. Something strange is definitely going on. Chiron realizes who Jason is and where he is from, but won't divulge anything. Soon all three friends are claimed by their godly parents, and they are sent off on a quest to save Hera from an unknown super-powerful enemy. All along, Jason is trying to discover who he is, where he's spent the past 12 years, and why each of them has been selected by Hera for this quest. The fulfillment of the second Great Prophecy is being revealed.
I truly savored this book, relishing the slow revealing of the parallel Roman aspects.