Psychological horror is a subgenre of horror and psychological fiction with a particular focus on mental, emotional, and psychological states to frighten, disturb, or unsettle its audience. The subgenre frequently overlaps with the related subgenre of psychological thriller, and often uses mystery elements and characters with unstable, unreliable, or disturbed psychological states to enhance the suspense, horror, drama, tension, and paranoia of the setting and plot and to provide an overall creepy, unpleasant, unsettling, or distressing atmosphere.