For instance, since I'd often wondered how the arms of the Venus de Milo disappeared, I decided to write a fictional story about the artifact--a tale about a heroine who arrived in England with one of the arms as proof she'd found a treasure.
My plan was to have thieves discover the arm, realize the potential value, and steal the proof of the find.The thieves would escape, although I didn't know where the broken piece of sculpture would go, or how the rest of the statue would end up in France.
So then I started writing, and...things changed. The outline went out the window.