Yes, there's entire books and segments of other books that were kept out at the council of Constantinople where they crafted the book of the bible we know today. Rather like a movie script based on an actual book.
I'm going to blow some minds right now
>These three lost sources may have been the first gospels. Their ancient
names are unknown, so they are usually identified by modern names,
specifically the Lost Q Source, the Pre- Markan Passion Narrative, and the
Signs Gospel. Because no copies of any of them have survived, they are
sometimes called hypothetical gospels. But most scholars believe that they
really did exist at one time.
>the Lost Q Source
https:// archive.org/stream/LostBooksOfTheBible/LostBooksOfTheBible_djvu.txt