Everything you need to understand or teach Hombre by Elmore Leonard.
Like most western fiction, Hombre develops a struggle between good and evil, and its final scene involves a confrontation of the forces that embody each. Society is shown to be a potentially inflammable mix of the two forces and periodically needs to be purged, even though the purgator sometimes dies in the process, a victim not just of society, but also of his own goodness. Commonplace western themes obviously are developed in Hombre, but the hero, atypically, does not ride off triumphantly into the sunset. More realistically, he turns out to be as much a victim as the villains are.