One minute, Jason, Piper, and Leo think they're on an ordinary field trip to the Grand Canyon with other kids from the Wilderness School -- a boarding school for troublemakers. The next minute, life as they know it completely changes. Jason has no idea who or where he is, and Piper and Leo can't understand why he doesn't recognize them. The three teens are then attacked by some kind of storm creatures, only to be rescued by total strangers who take them to a place called Camp Half-Blood. There, things get even more strange when the three friends learn that each one of them is a demi-god, with a Greek god for a parent. Maybe that explains why Piper is having alarming nightmares, why Leo is talking to ghosts, and why Jason has amnesia. To complicate matters further, a new threat to the gods and their demi-god offspring has emerged. Now it's up to Jason, Piper, and Leo to save them all.