Monstrosi-Dee Dee is the second part of the 3rd episode of Season 4 in Dexter's Laboratory, which aired on May 2, 2003. In this episode, Dee Dee eats one of Dexter's apples that he was using for his research project, turning her into a monster. She then helps Dexter hide. Dexter follows her advice, unaware that Dee Dee is actually the monster.
The title of the episode is a pun on the word "monstrosity" and Dee Dee.
It is assumed that the chemical effects of the contaminated apples eventually wore off on Dee Dee, as the episode doesn't seem to show her after Dexter panics and runs to warn his parents.
Mom & Dad eat the apples, yet the fate of their consumption was never followed up after this episode, similar to how Beetle Romania when Pumbaa eats Timon as a beetle again, yet the fate of his consumption was never followed up after this episode of Disney Television Animation's Timon & Pumbaa.
In the last scene of the episode, an old picture of the family can be seen behind Mom & Dad... Dee Dee is shown with only one pigtail instead of 2... this may be an error, or purposely imposed as logic to capture the early youth of Dee Dee and Dexter.
Dexter didn't know that the apples were contaminated.
It could be considered an irresponsibility of Dexter to throw the contaminated apples into the garden, because it is a clear violation of the laboratory's methods of dealing with biological, toxic or even radioactive wastes, making illogical that Dexter, a genius, would overlooked the appropriate process to eliminate biological wastes, like using a waste disposal or incinerator. Though, it is possible that he took this reckless decision out of anger from the failure of his experiment, or possibly proof that Dexter, despite being a genius, is negligent and inexperienced by being young.
This episode's gags are mostly visual, showing Dexter after being hidden in his machines for comedic effect.
Although this episode premiered in 2003, it was actually made in 2002 according to the credits.
These episodes completed production in August 2002.
The episode is an homage to the 1955 Bugs Bunny cartoon Hyde and Hare.