A sequel is a work of fiction (e.g. in literature or film) that is written after a completed work, and is set in the same "universe" but at a later time. It usually continues elements of the first story, often with the same characters, although this is not always the case - for example, if the main character dies at the end of the first work, a new character (e.g. their son or daughter) may take up their role in the sequel. A sequel is somewhat different from a series in which there is a long series of stories involving the same character, although some sequels have enough episodes to begin to resemble a series.

An example of a sequel is the novel Harry Potter and the Chamber of Secrets by J. K. Rowling. Since it is the second book in the series, and follows Harry Potter and the Philosopher's Stone, it is that novel's sequel.

Successful movies also have sequels, particularly horror, action and science fiction movies, as well as various comedies and westerns. The frequency of sequels of successful movies comes about in large part because it is seen as much less risky to reproduce a known success than to gamble with a new and untested story.

Often sequels are criticized as artistically inferior, and accused of simply repeating the story of the original film. However, sometimes a sequel gives an opportunity to address weaknesses in the original. For instance, the film Star Trek: The Motion Picture was panned as overlong, boring and short on character play. In reaction, Paramount Pictures hired Harve Bennett to produce a sequel that addresses the criticisms; he produced Star Trek II: The Wrath of Khan, which is considered one of the best films of the series. Other examples of sequels which are widely considered as good as or better than the original include The Godfather, Part II.

There are some common plot issues regarding sequels. Often when the original movie involves a character resolving a conflict, it is difficult to arrange the plot so that the characters face a similar problem.

Sometimes, the original film deliberately has story developments that a sequel could develop into future stories, such as in the film, Spider-Man. In that film, Peter Parker rejects Mary Jane Watson's love without explaining himself to protect her from his enemies while MJ is left with a suspicion that he is Spider-Man. If no sequels were produced, that development could have been treated as simply a tragic ending for the hero. However, with the film's success guaranteeing sequels, this ending provides the basis for a continued story arc in which the troubled relationship between the characters forms an important basis of future film plots.

With the recognition of the long term profitability of successful film series, most major films where sequels are expected have the major talents like the director and main actors contractorally obliged to participate in sequels. This increases the chance of the sequel being produced with at least the equivalent quality of the original film.

A related word, prequel, is used to describe something that portrays events which precede those of a completed work, i.e., the opposite of a sequel. Star Wars is the best-known film that has multiple prequels. A prequel can often avoid the plot problems associated with having to deal with the consequences of the original. An example of this involves the Planet of the Apes series of movies, where the entire earth was destroyed in Beneath the Planet of the Apes. The succeeding movies were therefore prequels. Prequels often have the problem of maintaining dramatic interest when the outcome is known, and often gather interest by attempting to show aspects of familiar characters that were not seen in the original.

The story that comes between two previously published works is called an interquel. This latter variation is less used than the other two.

See also

• Cliffhanger
• List of movie series
• List of movie trilogies