Suspense is a feeling of fascination and excitement mixed with apprehension, tension, and anxiety developed from an unpredictable, mysterious, and rousing source of entertainment. The term most often refers to an audience's perceptions in a dramatic work. Suspense is not exclusive to fiction. It may operate whenever there is a perceived suspended drama or a chain of cause is left in doubt, 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 a certain outcome to take place and have (or believe they have) a superior perspective on events in the drama's hierarchy of knowledge. Films having a lot of suspense belong in the thriller genre. In this case, suspense can be felt by knowing that a bomb has been planted in a car, and in some point in the future, it will explode while passengers are in it. The audience knows that there is a bomb in the car, but the characters in the film do not. Suspense is felt by the expectation that the bomb will explode at some point in the future, but they are not sure when. Suspense is the anticipation of the event with an uncertainty of the outcome and timing of the event.
In broader definition of suspense, this emotion arises when someone is unsure of what will happen in an 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 surprise. Suspense is knowing that an unfortunate outcome may occur some time in the future whereas surprise is the lack of knowledge with which something will happen at all until the moment that the event occurs that causes them to be surprised. Suspense could however be some small event in a person's life, such as a child anticipating an answer to a request they've made, such as, "May I get the kitty?" Therefore, suspense may be experienced to different degrees.
The typical suspense consists of having some real danger looming and a ray of hope. If there is no hope, the audience will feel despair.
The two common outcomes are:
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 (see Gerrig 1989, Walton 1990, Yanal 1996, Brewer 1996, Baroni 2007). 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 (see Brewer); 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 (Walton) or because we expect fictional worlds to look like the real world, where exact repetition of an event is impossible (Gerrig).
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 (2007: 279-295) 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).
In thrillers, suspense is the key element authors use to leave the reader or viewer hanging, trying to figure out what will happen next. The effect is specially strong when the work ends without actually revealing what happens next in the storyline.
Suspense is what gives a person the "on-edge" feeling. Suspense builds in order to make those final moments, no matter how short, the most memorable. The suspense in a story just keeps the person hooked into reading or watching more until the climax is reached, and the thrill and amusement of the suspension finally come to a close.
The tension doesn't have to be in the form of the villain stalking the hero. It can be much simpler, much less dramatic, but still make the person keep reading or watching. Suspense is about conflict, about the obstacles between the hero and their goal.