Definition of Thriller

Thriller is a broad genre of literature, film and television that includes numerous and often overlapping sub-genres. Thrillers are characterised by fast pacing, frequent action and resourceful heroes who must thwart the plans of more-powerful and better-equipped villains. Literary devices such as suspense, red herrings and cliff-hangers are used extensively. A thriller is a villain driven plot, whereby he presents obstacles the hero must overcome. The genre is fascinatingly flexible form that can undermine audience complacency through a dramatic rendering of psychological, social, familial and political tensions and encourages sheltered but sensation-hungry audiences.
en.wikipedia.org/wiki/Thriller_(genre)

Thrillers are often hybrids with other genres - there are action-thrillers, crime-caper thrillers, western-thrillers, film-noir thrillers, even romantic comedy-thrillers. Another closely-related genre is the horror film genre. Thriller and suspense films are virtually synonymous and interchangeable categorizations. They are types of films known to promote intense excitement, suspense, a high level of anticipation, ultra-heightened expectation, uncertainty, anxiety, and nerve-wracking tension.
www.filmsite.org/subgenres

A thriller is a book or film which is designed to keep the reader or viewer on edge with suspenseful and sensational action. Thrillers have also been produced in the radio, theatre, and television media. This genre is incredibly large, and thrillers often overlap with pieces of work produced in other genres; mysteries, for example, are often thrillers. Many people find thrillers very enjoyable, and they appreciate the fast pacing and complex plots associated with this genre.
Several characteristics help to define a thriller. Thrillers typically involve sudden plot twists and lots of red herrings, for example, keeping people unsure about what is going to happen. This suspense can get almost unbearable, especially in a long piece or a television series. Thrillers also have a lot of action, which is often chaotic, and they typically feature resourceful heroes and exotic settings.
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