Archeologists and historians have discovered certain books that have been banned or hidden throughout history for one reason or another. In some cases, the books are seen as too controversial, while in others, they are seen as being too subversive or dangerous. Whatever the reason, these books all have one thing in common: they are incredibly chilling. From the book of Enoch to the book of Soyga and the essential codex of Mendoza, these are the 15 most mysterious books in history.