A story arc (also narrative arc) is an extended or continuing storyline in episodic storytelling media such as television, comic books, comic strips, boardgames, video games, and films with each episode following a dramatic arc. On a television program, for example, the story would unfold over many episodes. In television, the use of the story arc is much more common in comedies, especially in soap operas. In a traditional Hollywood film, the story arc usually follows a three-act format. Webcomics are more likely to use story arcs than newspaper comics, as most webcomics have readable archives online that a newcomer to the strip can read in order to understand what is going on. Although story arcs have existed for decades, the term "story arc" was coined in 1988 in relation to the television series Wiseguy, and was quickly adapted for other uses.
Many American comic book series are now written in four or six-issue arcs, within a continuing series. Short story arcs are easier to package as trade paperbacks for resale and more accessible to the casual reader than the never-ending continuity that once characterized US comics. A corollary to the absence of continuity, however, is that, as exemplified in 1950s DC Superman comics, no permanent change to characters or situations occurs, meaning no growth can take place; thus storylines repeat overtime in an endless loop.
The purpose of a story arc is to move a character or a situation from one state to another; in other words, to effect change. This change or transformation often takes the form of either a tragic fall from grace or a reversal of that pattern. One common form in which this reversal is found is a character going from a situation of weakness to one of strength. For example, a poor woman goes on adventures and in the end makes a fortune for herself, or a lonely man falls in love and marries.
Another form of storytelling that offers a change or transformation of character is that of "hero's journey," as laid out in Joseph Campbell's theory of the monomyth in his work, The Hero with a Thousand Faces. Christopher Vogler's The Writer's Journey: Mythic Structure for Writers details the same theory specifically for western storytelling.
Story arcs in contemporary drama often follow the pattern of bringing a character to a low point, removing the structures the character depends upon and then forcing the character to find new strength without those structures. In a story arc, the character undergoes substantial growth or change, which culminates in the denouement in the last third or quarter of a story.