Jack and Annie must save stories that have been lost in history. Morgan, the magical librarian of Camelot, sends them to find the books in the ancient worlds of Roman Pompeii, imperial China, Dark Age Ireland, and classical Greece. Will Jack and Annie be able to save the stories in their darkest hours…or will the books be lost forever?

Books in this set include: Vacation Under the Volcano (#13), Day of the Dragon King (#14), Viking Ships at Sunrise (#15), and Hour of the Olympics (#16).