Being the author of a book and the showrunner of its TV adaptation definitely has its perks — you find to be the one to determine what to add or expand,what to shorten or lose altogether. For Neil Gaiman, adapting Good Omens, and the book he co-wrote with the late Terry Pratchett,this meant a veritable playground, where he got to add characters and scenes discussed with Pratchett that weren’t in the original novel.
Source: blastr.com