Bruce Bethke | Freelance Writer:
So the Deal with the Devil works like this: in exchange for your writer's soul, you get offered the chance to do a book that is almost guaranteed to be a huge, best-selling, commercial success. Confronted with this, most writers think "Okay, I'll do just one. Then, once I've got a best-seller on my resumé and the fans know who I am, I'll go back to doing "real" books."
Of course, as in all deals with the devil, there's at least one hidden catch, and the most important one is this: if the book is a huge, commercial, best-selling success, it gets credited to the media franchise that spawned it, whereas if the book tanks, it gets blamed on the writer. The other major catch is that there turns out to be little or no cross-over in readership. People who buy media tie-in books very rarely pay attention to books set outside of their favorite movie or TV universe. For example, Mike Stackpole tells me that fans send him email messages all the time gushing, "I've read ALL your books!" when what they really mean is that they've read all his STAR WARS books, and have absolutely no clue that he's written anything else and no interest in anything else in any case.