I'm kind of a planner. I don't go so far as to outline (usually), but I like to know my story roadmap along the way. I imagine scenes, make notes of upcoming scenes, and plan out the order of events to know when and where to reveal key details that will be needed later. This usually sets me in good stead for developing the story arc of an entire piece, but every once in a while a story element sneaks up on me.
I've got two pivotal scenes remaining in my current WIP, and while "planning" out (read: daydreaming in my car on the way to work) who would be in the first of those two remaining scenes, an idea popped up. An idea to plant a character in that scene that had previously been referenced but had yet to make an appearance. And of course, my first thought was:
Why is this character here? What happens if this character is here?
And then it all unfurled like a great majestic cloak to finish out my story. Because as soon as I placed that character in the scene, I knew why they were there and, more importantly, what their presence would do to the rest of the story. It gave my villain motive, it set up future story ideas, and it closed out the story in a way that I never saw coming. As a planner, I was floored.
My story just told me what to do.
I've seen other writers reference the whole concept of letting your characters tell you where the story is going, but I'd honestly never put a lot of stock in it. To me, if I just let my characters roam across the page without any direction I'd end up with a few thousand words of witty banter, random descriptions, and not a whole lot of plot movement. My approach has always been to make things happen to my characters and see how they react. This is the first time I've ever really had a character tell me what they were going to do, and why. It was an amazing, bizarre experience that I hope to encounter again very soon.
How do you plot? Do you let the characters tell you what's going to happen, or do you make things happen and wait to see how they react? Do you grow your stories organically or are you a plotter? Have you experienced this moment yourself?