This set of 5 books consists of the 5 Percy Jackson books that were # 1 on the NY Times Best-Sellers list. The set is called "Percy Jackson and the Olympians: The Complete Series". Extremely popular with upper elementary and middle school students. Set is available in a cardboard jacket. Titles consist of # 1 The Lightning Thief; # 2 The Sea of Monsters; # 3 The Titan's Curse; # 4 The Battle of the labyrinth; # 5 The Last Olympian. Retails for $35.00 !!