Rick Riordan

In this Percy Jackson mini adventure first published in The Demigod Files, the goddess Persephone summons Percy, Thalia, and Nico to the Underworld to retrieve Hades's powerful sword before it falls into the wrong hands. Easier said than done in a realm full of daimons, ghosts, and monsters. Not to mention …

Percy Jackson and the Olympians 5-book Boxed Set is a collection of books written by Rick Riordan. The set includes the best-selling The Lightning Thief, The Sea of Monsters,The Titan's Curse, The Battle of the Labyrinth, and The Last Olympians.