 They were trying to hide an ancient tome written in multiple languages called The Book of Changes, in Zoe's house (Zoe was unknowingly the destined caretaker).Eli then became the caretaker of the book, and was warned by one of the Watchers (Carl) that people were after the book, he must safeguard it and was also warned he must not show it to Melinda.Melinda, however, couldn't get the idea something was wrong out of her mind and convinced Eli to show her the book.