A nature documentary team observes “Blackfoot” (Dexter) and “Slim” (Dee Dee) in their “natural habitat”.

Dee Dee goes and plays in her own “lab” after being kicked out of Dexter’s.

Dexter’s school and parents decide to send him to college. He ignores his fellow students, who prefer to “party now, study later”, until his mind finally snaps from the workload.

Dexter’s lab is threatened with repossession unless he can repay his debt to NASA. When Dee Dee wins the same amount in a lottery, he decides to steal her money out of desperation.

Valhallen loses his magic ax and starts turning into a nerd, forcing Major Glory and Krunk to enter his room to find it.

To fix their apartment’s plumbing, Krunk and Valhallen go to the basement, where they meet Ratman (Maurice LaMarche), a diminutive vigilante raised by rats (a parody of Batman).

Mandark enters a surfing contest and tries to cheat his way to victory to win Dee Dee’s heart from another surfer.

After working in his lab all night creating his latest invention, Dexter tries to sleep, but he is constantly interrupted by Dee Dee.

Dexter is given detention after accidentally shouting out the answer to a test question.

Dexter makes an angst-ridden trip to the hardware store to buy a new light bulb for his lab.

Dee Dee gets a song stuck in her head, which is actually a virus. Dexter and Mom soon catch it, and Dexter has to reverse the effects of this. He succeeds at the end, not knowing that Dad also caught it.

In a parody of Tom and Jerry, Dexter accidentally switches his brain with that of a mouse’s and must avoid his mother when she decides to exterminate him.

Dexter and Dee Dee protect their mother’s muffins from their muffin-loving father while she is out shopping.

Dexter is forced to take Dee Dee to the zoo. There, she ends up trying to save an ostrich with disastrous results. Dee Dee and the ostrich switches their places.

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.

When Dexter’s father tries to teach his son sports, he realizes that Dexter is not athletic.

Dexter tries to prove to Dee Dee that Santa Claus is not real and is in fact their father in disguise. He ends up paying for his mistake when he has captured the real Santa Claus.

Monkey must defend the city from a giant underground lava monster, Magmanamus (Brad Garrett), who cannot sleep because of the noise created by its residents.

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.

Dexter is trapped in his school by the janitor in revenge for making him work late everyday due to Dexter’s habit of leaving the school last everyday.

Dexter tries to improve his eyesight by giving himself laser eye surgery, but goes too far in doing so.

Dexter thinks that a crazy homeless person balancing electronic devices on his head and muttering gibberish is a genius trying to contact aliens, so he takes him home.

Dexter is upset that Dee Dee is more photogenic than him, so he transforms his face into a handsome one for his next Picture Day.

While on a date with Agent Honeydew, Monkey gets hypnotized by the music of the Organ Grindor (Jim Cummings), who commands him to rob Fort Knox.