When Dorrie and her brother Marcus chase her pet mongoose into the janitor's closet of their local library, they accidentally fall through a passage into Petrarch's Library -the headquarters of a secret society of ninja librarians who have an important mission: protect those whose words have gotten them into trouble. Anywhere in the world and at any time in history.Dorrie would love nothing more than to join the society. But when a traitor surfaces, she and her friends are the prime suspects. Can they clear their names before the only passage back to the twenty-first century closes forever?