Key hunters

Neither Cleo nor Evan like the new school librarian, Ms. Crowley, but they are 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 is 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.

This time Cleo, Evan, the evil Mr. Locke, and his two trolls have all been transported to the Titanic--and if they do not find and save the priceless jeweled copy of the Rubiyat before the ship hits the iceberg and sinks they may all be lost at sea.

Despite the evil Locke, Cleo and Evan manage to get Gabriel back to his world, but it is a world that is controlled by a computer network which is connected by a device called a Neuro-Zip implanted in the skull of every human being in the world--every human except for Cleo and Evan, so it is up to them to bring down the Network, and return control to the human population.