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 …

From New York Times #1 best-selling author Rick Riordan and award-winning author Mark Oshiro comes a new standalone adventure featuring two of the most popular characters from the world of Percy Jackson and the Olympians. ONE PROPHECY. TWO DEMIGODS. A HEROIC QUEST. Nico di Angelo is pretty familiar with the realms of …