The evil wizard Maldred has stolen the gold and silver keys which will allow him to release the Naga, the powerful earthquake dragon at the center of the earth--so Drake and several of the other Dragon Masters travel to the Naga's Temple in the Dragon Islands, to try and stop Maldred, and prevent him and the earthquake dragon from destroying the kingdom.

Neither Cleo nor Evan like the new school librarian, Ms. Crowley, but they're very curious about where she disappears to at the back of the library, so one day they follow her--and find a secret door, a magical library full of locked books, and a letter from the previous librarian telling them that she's trapped somewhere between the covers of one of the enchanted books, and they must travel through the stories in order to save her.

In their third trip through the enchanted library, Cleo and Evan land in "The Werewolf's Curse" where Evan is promptly bitten by a werewolf, and the two need to find the cure--and the next key--before the full moon rises and Evan becomes stuck in this horror story forever.

In search of a key to unlock a box from her late mother, Clara finds her way into a mysterious parallel world. She teams up with a soldier named Philip in order to brave the Fourth Realm to find the key and return harmony to the unstable world.

This time Cleo, Evan, and Ms. Crowley (who, it turns out, is the missing Ms. Hilliard's sister) find themselves in a confusing fantasy book, caught up in a war with wizards, elves, trolls, and the mighty Golden Dragon-- and while they manage to find their missing librarian, their quest does not end there.