The House of Hades | Riordan Wiki - riordanom OverviewDevelopmentSynopsisThe House of Hades is the fourth book in The Heroes of Olympus series. It was released on October 8th, 2013. The book takes place after The Mark of Athena.See more on riordanom · Text under CC-BY-SA license The House of Hades – Rick Riordan The House of Hades. The other five demigods have to put aside their grief and follow Percy’s instructions to find the mortal side of the Doors of Death. If they can fight their way through the Gaea’s forces, and Percy and Annabeth can survive the House of Hades, then the Seven will be able to seal the Doors both sides and prevent..