The Lost Hero
Rick Riordan
The Heroes of Olympus (1)
The Battle of the Labyrinth
Percy Jackson and the Olympians (4)
The Last Olympian
Percy Jackson and the Olympians (5)
Titan's Curse, the (Percy Jackson and the Olympians, Book 3)
Percy Jackson and the Olympians (3)
The Sea of Monsters
Percy Jackson and the Olympians (2)