The Secret Book Series is a series of book that tells the secrets of everyone at the Cartoon House.
The series was created by Embless and Rief. It is seperated by people. Each person has a series of book on them, updated as time passes and more history of that person is made. While it is no longer worked on, the series still has a few copies around and is available on Rief's computer.
The Secret Book Series was the basis for season five and made many appearances in it.
In season seven, Issac and Garet asked Rief and Embless if they could borrow Felix and Sheba's books to try to get them together. Embless actually gave them a page from Sheba's book, which revealed that Sheba likes pulling pranks on people.