Some of the best horror movies speak to fears lingering beneath the surface of society. The way in which early examples of the genre whitewashed the often brutal landscape of the frontier is, at the very least, slightly unsettling in hindsight. As things went on, the films continued to indulge this darker sensibility, and in the process we got some of the best Westerns ever made. Paul Newman's darkest Western is a must-watch masterpiece, and the controversial, disturbing Western "El Topo" won plaudits from the great Roger Ebert. But there are even darker examples, and we've ranked the top five while trying to include a mix of styles from the psychological to full-on Western horror.