The 'Heroes of Olympus complete collection (5 book slipcase)’ is a set of 5 books that will grip the reader's thanks to its engaging storytelling and unique narration. It includes the books - The Lost Hero, The Son of Neptune, The Mark of Athena, The House of Hades, and The Blood of Olympus. This book series describes how Camp Jupiter and Camp Half-Blood battle with Gaea, the goddess of the Earth, and saves the world. The plot is based on the prophecy introduced in The Last Olympian which stated that seven demi-gods will eventually unite and save the world.