Playing With / Retcon

Basic Trope: Revising or rewriting past events or canon elements to serve a current plot need.
  • Straight: In the first two seasons of the show Bob's Crazy Adventures, Alice and Bob are cousins. Starting in the third season, Alice and Bob are a Sibling Team, and they have a cousin named Claire who didn't exist in earlier episodes.
  • Exaggerated: The show undergoes several mid-season retcons during its run, and the stars Alice and Bob are the only characters common to every season of the show.
  • Downplayed: Alice's appearance changes in the fourth season.
  • Justified: It's an altered reality.
  • Inverted: The writer reverts the canon to its previous version.
  • Subverted:
  • Double Subverted:
    • When Bob wakes up, we see that a completely different retcon is in effect.
    • The writer makes the third season canon due to its popularity.
  • Parodied: ???
  • Zig Zagged: ???
  • Averted: Nothing is rewritten.
  • Enforced: This is done to omit countless Plot Threads that would be nearly impossible to resolve.
  • Lampshaded: "The new season of Bob's Crazy Adventures: It's Bob like you've never seen him before!"
  • Invoked: Peggy Sue
  • Exploited: ???
  • Defied: The Status Quo Demon prevents all retcons.
  • Discussed: "Something doesn't feel right here..."
  • Conversed: "Why is this show so different from what it used to be? It's like the characters have nothing in common with their old versions, except for the names."
  • Deconstructed: A fan writes a Fix Fic which uses the old canon.
  • Plotted A Good Waste: The writer decides to leave a mistake in.

Everything you knew about Retcons is wrong! See for yourself!
http://tvtropes.org/pmwiki/pmwiki.php/PlayingWith/Retcon