retcons

Retcon, short for retroactive continuity, is a narrative technique in which past events or details in a fictional universe are revised or reinterpreted after the fact. Retcons are used to resolve contradictions, account for new creative directions, or align a story with a broader plan.

Retcons vary in how they affect the past. A hard retcon changes or erases previous events; a soft retcon reinterprets or expands them without fully reversing what happened, often with in-universe justification. Retcons can create multiple canons or alternate timelines, leading to debates about what is considered true within the fictional world.

In practice they appear across media, including comics, television, movies, and video games. Famous examples include DC Comics' Crisis on Infinite Earths, which rebooted much of the DC Multiverse; Marvel's One More Day (2007), which retconned Spider-Man's marriage; Dallas's widely discussed dream season, cited as a non-canonical retcon; and various Star Trek timeline revisions added by later series and films to align continuity.

Retcons can be controversial among fans, sometimes triggering debates about canonicity and the integrity of earlier storytelling. Proponents argue that retcons help maintain coherence as franchises expand or shift direction, while critics contend they disrupt established characterizations or undermine previous narratives.