Foreshadowing is a literary device in which an author drops subtle hints about plot developments to come later in his story. Each of these hints widens the range of possible consequences and maintains tension throughout the narrative as these possibilities narrow. When these hints are designed to mislead the audience into thinking something will transpire other than what actually does, it is referred to as a red herring.

An example of foreshadowing can be when a character uses a gun or knife early in the play/film/narrative. Merely the appearance of a deadly weapon, even though it is used for an innocuous purpose - such as being cleaned or whittling wood - suggests terrible consequences later on.

See also: prolepsis, Chekhov's gun