Geronimo Stilton finds a golden staircase in his attic with a door at the top of the stairs. Beyond the door is the Kingdom of Fantasy! Geronimo sets off on an incredible adventure to save the Queen of the Fairies, facing giant scorpions, witches, sea serpents, pixies, and dozens of other fantastical creatures along the way.

Once again Geronimo Stilton is pulled into the Kingdom of Fantasy, where he is needed to fulfill the ancient Gemstone Prophecy, and prevent Scorcher, the evil Empress of Witches, from obtaining the Royal Sapphire which will give her immense power.

After receiving a mysterious message summoning him to a meeting, Geronimo Stilton finds himself back in the Kingdom of Fantasy, summoned by the Elves, who want him to travel to the Great Explanatorium to find an answer to the earthquakes that are threatening the Kingdom.

"Geronimo has to face his worst enemies, the Pirate Cats, who have discovered a way to travel back in time and change history...they want to change the face of the Great Sphinx into a cat's face. Can they possibly trick th pharaoh Chephren into making this happen? And how can Geronimo Stilton possibly stop them?"--P. [4] of cover.