Frame story: A story that contains another story or stories. Usually, the frame story explains why the interior story or stories are being told. For example, the frame story in The Thousand and One Nights (also known as The Arabian Nights) (c. 1450) explains that Queen Shahrazad tells her husband, King Shahryar, a story every night — each one ending with a reference to or preview of the story to be told the following night — because the King has had over a thousand previous wives executed the morning after the wedding night in order to ensure that they would never be unfaithful to him, as was his first wife.
The degree to which the frame story has its own plot varies; that is, the frame story may be extremely sketchy or fairly well developed. The interior stories are likely to be fully developed tales, usually completely separate from one another (except insofar as they are linked by the narrative frame and sometimes by theme or subject matter).
FURTHER EXAMPLES: Panchatantra (c. A.D. 500; anonymous), Boccaccio’s Decameron (1348—53), Geoffrey Chaucer’s Canterbury Tales (c. 1387), Marguerite de Navarre’s Heptaméron (1548), and Joseph Conrad’s Heart of Darkness (1899). Movies such as Invasion of the Body Snatchers (1956) and The Princess Bride (1987) make use of frame stories, as do Titanic (1997), Adaptation (2002), and The Reluctant Fundamentalist (2013).