Suspense is a state of mental uncertainty, anxiety, being undecided, or being doubtful. In a dramatic work, suspense is the anticipation of the outcome of a plot or of the solution to an uncertainty, puzzle, or mystery, particularly as it affects a character for whom one has sympathy. However, suspense is not exclusive to fiction.
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.
Some authors have tried to explain the "paradox of suspense", namely: a narrative tension that remains effective even when uncertainty is neutralized, because repeat audiences know exactly how the story resolves. Some theories assume that true repeat audiences are extremely rare because, in reiteration, we usually forget many details of the story and the interest arises due to these holes of memory; others claim that uncertainty remains even for often told stories because, during the immersion in the fictional world, we forget fictionally what we know factually or because we expect fictional worlds to look like the real world, where exact repetition of an event is impossible.
The position of Yanal is more radical and postulates that narrative tension that remains effective in true repetition should be clearly distinguished from genuine suspense, because uncertainty is part of the definition of suspense. Baroni proposes to name rappel this kind of suspense whose excitement relies on the ability of the audience to anticipate perfectly what is to come, a precognition that is particularly enjoyable for children dealing with well-known fairy tales. Baroni adds that another kind of suspense without uncertainty can emerge with the occasional contradiction between what the reader knows about the future (cognition) and what he desires (volition), especially in tragedy, when the protagonist eventually dies or fails (suspense par contradiction).