When Dee Dee claims that anything can be hers because Dexter “doesn’t have his name on it”, he invents a label-making gun.

When Dexter learns that Dee Dee is trying to make a science project alone, he decides to help her, but she does not want his help.

While out for dinner at a pizza restaurant, Dexter tries to slow down the “Whack the Weasel” machine to win a stuffed Monkey doll before Dee Dee does. Security captures him for tampering with the machine, and he falls into the hands of a mad scientist.

When Dexter neglects his metal-eating pet bug, it begins eating his lab as revenge.

Dexter’s new device allows him to study for the next day’s French test while sleeping. It malfunctions, causing a single phrase (omelette du fromage) to repeat throughout the night, causing Dexter to wake up the next morning speaking nothing else except omelette du fromage.

After a crime prevention talk at school, Dee Dee, Lee Lee, and Mee Mee become crime fighters, but they unintentionally end up being neighborhood criminals.

Dexter accidentally gives himself telepathy that he cannot shut off when trying to overhear his father’s thoughts to figure out what he got for his birthday, causing everyone to accidentally read his own mind.

When his mother falls ill, Dexter creates a robot to do her chores. Dee Dee gets hold of its remote control and wreaks havoc, forcing Dexter to create a second robot to counter Dee Dee’s.

Suspicious that Dee Dee has not entered his lab even once on a particular day, Dexter shrinks himself and enters her room to spy on her. He soon becomes an unwilling character in Dee Dee’s doll story, but he believes the story to be real.

Dexter finds the exact opposite of his family, a hyperactive boy who is like Dee Dee and has scientist parents who are like Dexter. Sensing to fit in, he switches places with the boy.

Dexter’s father tries to get himself and Dexter to his fishing spot before sunrise so that they can start fishing before others arrive.

Dee Dee and her friends, Lee Lee and Mee Mee, enter Dexter’s lab and wreak havoc. Dexter clones himself to stop them, but the girls too make clones of themselves.

Parodying The Pink Panther, Dexter is trying to paint his lab blue, but Dee Dee wants to make it pink.

Dexter creates a device to make a lifelike superhero comic, with his sister villain “Deestructa”.

To learn more about girls, Dexter camouflages himself and enters Dee Dee’s room, where she is having a sleepover with her friends Lee Lee and Mee Mee. He gets caught by the girls, who force him to take part in their activities.

When Dexter and his friends go looking for a “Star Check” convention, they accidentally end up at a “Darbie” doll convention.

Dexter turns Dee Dee into a boy, but is disappointed when “he” is not a genius as Dexter would like it.

Mandark brings his lab duck Ducky for show and tell to counter Dexter and his lab monkey. Though neither creature displays remarkable characteristics at school, Ducky, unbeknownst to Mandark, is the alter ego of supervillain Quackor the Fowl.

Dexter finds out that all of Mandark’s plans are taken from a comic book.

Dexter and his friends are targeted by a bully at school for their multicultural accents.

Dexter is disappointed when he ends up at an Amish farm instead of a high-tech farm for summer camp. His attempts to modernize the Amish family do not go well.

Dexter accidentally becomes Dee Dee’s foot when the two fuse together. Now, they have to wait 24 hours to reverse the fusion.

A teleporter malfunction sends Dexter to an alien prison, prompting Dee Dee to go on a mission to save Dexter.

Dexter’s life story, from his birth to the creation of his secret laboratory, is retold as an opera.