Suspense is a feeling of uncertainty and anxiety about the outcome of certain actions, most often referring to an audience's perceptions in a dramatic work. Suspense is not exclusive to fiction, though. Suspense may operate in any situation where there is a lead up to a big event or dramatic moment, with tension being a primary emotion felt as part of the situation. In the kind of suspense described by film director Alfred Hitchcock, an audience experiences suspense when they expect something bad to happen and have (or believe they have) a superior perspective on events in the drama's hierarchy of knowledge, yet they are powerless to intervene to prevent it from happening. In broader definitions of suspense, this emotion arises when someone is aware of his lack of knowledge about the development of a meaningful event; thus, suspense is a combination of anticipation and uncertainty dealing with the obscurity of the future. In terms of narrative expectations, it may be contrasted with mystery or curiosity and surprise.