When a mysterious wind blows the pages of a book stolen long ago from the Biblioteca Maldita, it turns them into sharp, bat-like objects that fly on their own, and only the Librarian can stop them from attacking a young reader.
When the Librarian returns to his castle after lengthy travels, he finds that someone has stolen his collection of deadly books, and until he can get past a beast the thief left behind and track them down, the world is in great jeopardy.
When a girl starts reading a strange book someone left on a bus, she suddenly finds herself inside its pages, where the Librarian shows her how to avoid the poisonous letters and other dangers.
Some books are so evil that they must be imprisoned deep underground, but when the Librarian tries to dispose of one vile volume, he risks being buried alive in an eerie tower that holds a legendary secret.