Just put the finishing touches on Chapter 12 of my WIP, which was a totally unexpected project, and may have zero chance of being marketable.
Fifty years ago I read a book by a famous author, and it was written 16 years before that. I've always been dissatisfied in the conclusion to the book, because it left a young character's future completely open, with his primary aspiration unfulfilled. Here's problem number one: it may be my favorite book. If not, it's on a very short list.
The author never wrote a sequel, and I realized a LONG time ago that if there were to ever be one, I'd probably have to write it. This brings up problem number two. He was a great writer, and I knew I wasn't up to following up that book. Writing cheesy fan fiction isn't my thing.
Ten days ago, I had just finished proofing my latest, wondering what to do next. I read that book again, and while it may sound insane, or insanely self-possessed, I decided I could write a sequel which compares favorably to the original. I opened up Word, wrote the first line, and the rest has come along like I'm channeling. Ridiculous. I've written almost 50K words in ten days, and while I don't think I can maintain that pace, I should finish inside of another two weeks.
When I started, I decided on a tentative scope for the story, but I didn't plot it. Remember, I probably can't market this manuscript. The estate has been very stingy in that regard. I'm pantsing it for the purpose of "sort of" reading it as I go. LOL If nothing else ever comes of it, I have the satisfaction after 50 years of FINALLY knowing what happened to the hero of that novel, and that satisfies me. I have a few friends who are also big fans of the author, and they are eager to get a crack at it, as is my wife. So at least I'm writing for a very small audience.