The Sword of Hades

Percy Jackson and the Sword of Hades is a short story in the Percy Jackson series. It was written for World Book Day 2009 and was written by Rick Riordan. It takes place between The Battle of the Labyrinth and The Last Olympian. It shares a book with the WBD Edition of 'Horrible Histories: The Groovy Greeks'. It was available from March 2nd to March 29th 2009 in the UK.

New York
Percy was taking a test at Goode High School, when Mrs. O'Leary, Percy's pet hellhound from The Battle of the Labyrinth, comes barging in. Luckily, thanks to the Mist, everyone thinks it's a poodle. Percy quickly takes it outofd the school. Suddenly a golden deer appears, and Thalia is chasing it. When they notice each other, Nico comes out of the bushes, apparently transported from New Orleans. Suddenly the ground opens up, and Percy, Thalia and Nico fall into it.

Persephone
They end up in the Underworld, where Persephone, from the myths, appears to greet them. She tells them that Hades is forging a new sword which allows things to enter and exit the Underworld using one of Hades' Keys. Unfortunatly, it has been stolen. The sword was meant to be secret, so no one knows about it, let alone know it's stolen. Persephone suspects a demigod on Kronos' side to have stolen it. She gives Percy a flower. It helps track down the sword, but if all the petals fall off it, the sword is out of the Underworld and doomsday is near. So Percy, Thalia and Nico set off to find the sword.