In literature, films, television, and plays, suspense is a major device for securing and maintaining interest. It may be of several major types: in one, the outcome is uncertain and the suspense resides in the question of who, what, or how; in another, the outcome is inevitable from foregoing events, and the suspense resides in the audience's anxious or frightened anticipation in the question of when. Readers feel suspense when they are deeply curious about what will happen next, or when they know what is likely to happen but don’t know how it will happen. Even in historical fiction, with characters whose life stories are well known, the why usually brings suspense to the novel.
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