I've given this assignment, in various incarnations, for over 20 years, and my students seem to enjoy it. I use it around Halloween, but it also works well with units involving gothic literature, like the novel Frankenstein or the works of Edgar Allan Poe. I have also used it with Jane Eyre.
The product contains six files:
(1) the writing prompt that is the central focus of the assignment (including a scoring guide),
(2) three PowerPoint presentations to help you guide students through the writing process (one on setting, one on characterization, and a cooperative learning activity designed to get students excited about writing),
(3) a handout that provides two exemplars and a close reading activity,
(4) and a unit plan to show you how I use all of these materials (in Word).