Authors typically build a reputation within a particular genre or style of book. Brandon Sanderson, for instance, is known as a prolific writer of fantasy novels, often with detailed magic systems, and but for occasional dabbles into science fiction, writes little else.

But even when firmly established in one genre, some authors like to experiment and do something totally different (some will even use a pseudonym to differentiate these curveballs from their usual fare, as Stephen King did when writing under the name Richard Bachman). What we want to know is: what are the most surprising, radical, genre-breaking, or otherwise interesting 'curveball' books from writers who were known for doing something totally different?

Name at least one book (or comic!) that represented a radical change in direction from an established author and tell us a little bit about it. Why was it such a shift? Why did the author change tack? Was it successful?