Retroactive continuity

Retroactive continuity, or retcon, is a literary device in which established facts in a previously published work are changed by new information in a later work, altering how earlier events are interpreted. The article lists motivations including accommodating sequels, responding to negative fan reception, and correcting errors. Examples include Arthur Conan Doyle bringing back Sherlock Holmes in "The Empty House" in 1903 after killing him off in "The Final Problem" in 1893, and the TV series Dallas annulling its ninth season as the dream of Pam Ewing so that Bobby Ewing could return. The first known use of the term in fiction appeared in DC Comics' All-Star Squadron #18 in February 1983.