Horror films commonly use certain iconography like haunted houses, knives, and depictions of blood and death. They are usually set in dark and isolated places at night that make people feel vulnerable, like abandoned buildings. The narrative typically involves a monster terrorizing a group of people in a battle of good versus evil. To build suspense and mystery, horror movies employ scary sounds and point-of-view camera shots. They often feature supernatural killers targeting female or young adult victims. Recurring themes are struggles between good and evil or other moral dilemmas.