backstory
n. An underlying narrative that provides the background or historical context for a novel, screenplay, or other story.
Also Seen As
Etymology
Examples
1999
Further blurring the distinction between reality and fiction, Mynick and Sanchez followed the movie's post-production by designing an elaborate Internet site that offers supplementary backstory information such as video clips of outtakes, a history of the Blair Witch and what purports to be visual evidence of the student film-makers' fate.
—Michael Dwyer, “Mock Horror,” The Irish Times, August 14, 1999
1982 (earliest)
Christopher Reeve, who plays the miracle man from planet Krypton, portrays a homosexual in his new movie, ''Deathtrap.'' In one love scene he kisses Michael Caine smack on the mouth. Yech!

What kind of response will this wrest from millions of adoring fans of The Man of Steel? Will they continue to exclaim, ''It's a bird! It's a plane! It's Superman!'' Or will they simply make sly remarks about Superman's flights.

Not the least worried about such speculation is actor Reeve who says the vault from Superman to homosexual is no quantum leap. It is, he avers, a mere hop, skip and a jump.

''You have to know the back story of my career before you can pass judgment on the roles I play,'' said the erudite New Yorker.
—Vernon Scot, “Scott's World: Superman Kisses A Guy!,” United Press International, April 03, 1982