Retroactive continuity (often shortened to retcon) is the deliberate changing of previously established facts in a work of serial fiction. Retconning may be carried out for a variety of reasons, such as to accommodate sequels or further derivative works in the same series, to reintroduce popular characters, to make a reboot of an old series more relevant to modern audiences, or to simplify an excessively complex continuity structure.
Retcon and OddParents continuity
The Fairly OddParents has a very volatile continuity. What is established in one episode, and then further supported in a later episode, may still be contradicted in a later episode. Most often the case is "Da Rules", the list of restrictions to fairy magic that Timmy and his godparents must abide by. Many of these rules are simply established for the sake of a plot in one episode, and bringing these rules up again would be redundant. In most cases, the rule is there to prevent Timmy from simply wishing his problem away without taking action first, but in some cases an established rule may prevent the plot of a whole other episode from being possible, so that particular episode will simply ignore that rule.
Another example is established facts about characters. Much of the history of the fairy folk, their biology, and their relationship with godchild, has been changed over the years to the point where it is almost impossible to write off something mentioned in a single episode as fact unless it is common knowledge (i.e. fairies use magic). Minor characters that are used over many episodes may appear to act completely different between episodes, even those in the same season. This is because OddParents has many different writers who work on one or two episodes per season between each of them, and in the decade that OddParents has existed, the writer pool has been shuffled and completely replaced several times over. What one writer might establish as fact about one character, another writer will completely overlook or disregard for the sake of plot integrity, humor, or even personal feelings.
- Main article: List of The Fairly OddParents plot retcons
- When Timmy first met Cosmo and Wanda, he was ten years old, and it was the first day he had ever been babysat by Vicky. This was established in the pilot episode and supported in "Deja Vu", but in "Abra-Catastrophe!" it was shown that Timmy was much younger when Vicky first started babysitting him, and he received his godparents at age nine.
- The Secret Origin of Denzel Crocker reveals a large part of Mr. Crocker's backstory, most of which has already been contradicted. In "Birthday Bashed", Mr. Crocker had fairies other than Cosmo and Wanda as a kid, and did not lose them by accident.
- Vicky mentions having a little brother in the pilot episode, but all episodes which have shown her entire family have never shown her having a brother. This character was likely scrapped and replaced by Tootie.
- Dad's Office Building eventually became or was replaced by Pencil Nexus.
- The Gland Plan establishes that Cosmo is an only child, but Double Oh Schnozmo reveals he has an older brother.