The Lost Hero (The Heroes of Olympus)

Jason has a problem. He doesn't remember anything before waking up in a bus full of kids on a field trip. Apparently he has a girlfriend named Piper, and his best friend is a guy named Leo.

Piper has a secret. Her father, a famous actor, has been missing for three days, ever since he had that terrifying nightmare about his being in trouble. Piper doesn't understand her dream, or why her boyfriend suddenly doesn't recognize her.

Leo has a way with tools. When he sees his cabin at Camp Half-Blood, filled with power tools and machine parts, he feels right at home. But there's weird stuff, too-like teh curse everyone keeps talking about, and some camper who;s gone missing.