I went the extra step and wrote a two-page treatment for my film. It takes place in the dreary Pacific Northwest and involves a psychopathic serial killer who poses as the friendly, local weatherman in order to get closer to his victims. His weapon of choice is the umbrella owned by each of his victims. Using their personal umbrellas allows him to make each gruesome murder scene look like a freak, rainy day accident. The plot takes a disgusting twist when he decides to start fabricating umbrellas with the skin of his victims.
So, I figured creating a very simple graphic, focused on an umbrella and raining blood, was a nice way to go for my poster. And, of course, I needed to write a cheesy, horror movie tagline to finish it off.