The Kids Next Door attempt to stop a party for their enemies.

The KND learn about evil mustaches taking over the faces.

The Delightful Children once again hold their annual birthday party in the usual sadistic manner planning to eat their cake and not let any of their unwilling guests have so much as a taste.

Numbuh 2 has always been one of the best pilots in the organization but one day while taking his 2X4 aircraft for a spin, he's shot down by a mysterious child pilot with a 2X4 plane of his own. 2 seeks revenge, but the pilot is untouchable, and manages to shoot him down out of every aircraft in the team's arsenal. Considering giving up, piloting, finally finds a way to defeat the pilot only to discover that his supplier has been fooling them both into fighting each other in a plot to destroy every chili dog in town!

Numbuh 4's disgust at anything Rainbow Monkey only increases when he finds himself trapped on Rainbow Island.

Numbuh 4 learns he is to be sent to a boarding school but he isn't worried, as he's always escaped from them before. But then he learns that the school is being run by the evil child Madam Margie, a girl who is getting high-tech aid from none other than her future self! Madam Margie's abominable plan is to create a twisted utopia where girls rule the world, using a demonic weapon called the girlifying ray that can turn anything feminine! The team seeming doesn't stand a chance until they recieve aid from a strange source Numbuh 4's OWN future self!

A dinner get-together between Numbuh 2 and Numbuh 3's respective families turns sour when Numbuh 3's Posh Party Rainbow Monkey doll is badly damaged with a fork in its back. Now it's up to Numbuh 2 to figure out the murderer of the doll.

Numbuh 4 discovers a chicken nugget that initiates a chicken nugget rush.

Everyone's collections of Rainbow Monkey toys are mysteriously vanishing. The KND investigate and discover the toys revolving around the planet Saturn as its big ring!

Nigel is exhausted and dirty after a hard mission, and when he takes a break, Lizzie intercepts a mission spec from Numbuh 65.3. Deciding to give Nigel a break, Lizzie tricks the rest of the team into thinking Nigel put him in charge, and assumes the role as leader. But Lizzie i

The evil Chester is developing his Happy Headband a strange device he plans to sell to parents to keep kids out of their hair.

Numbuhs 2 and 5 must rescue the first grade class's pet rabbit before it is turned into a chocolate bunny by Heinrich Von Marzipan.

Numbuh 4's newly-installed backyard pool is the portal into an alternate dimension where everything is the opposite of everything in the real world.

At the KND Arctic training facility (the second largest KND base in existence, and location of the top secret KND Code Module), young cadet Tommy is

Numbuh 3 takes her little sister Mushi for a ride through the Rainbow Monkey Sugar Coated Castle of Love, but what promises to be a day of fun is ruined when King Sandy and his knights attack! The insane sovereign has never given up in his quest to marry Numbuh 3, and he threatens to destroy the Rainbow Monkeys unless Kuki agre

The villains attempt to capture the KND Treehouse, but the Toilenator, trying to be helpful, only hinders their plans.

The KND are dismayed to discover that Grandma Stuffum is the new cafeteria lunch lady and she's got some pretty nasty recipes to foist on her pint-sized nemeses.

Numbuh 5 goes to the planet Mars to pick up some marshmallows as part of dessert with her family after dinner. But upon her return, she discovers her family and friends are being menaced by an old foe who now is a mere shell of his old self.

It's time for the morning commute to school, and for once, Numbuh 4 is anxious to go, mostly because he has a crush on the new teacher. But on the way to school, the bus is attacked by kids dressed by cowboys packing chewing-gun loaded six-shooters, demanding the students' spelling homework! Now Numbuh 4 pursues the bandits outside, while Numbuh 5 engages them on the bus itself. Can they save the day before first bell? And who is the brains behind these delinquent desperadoes?!

The true history of the genesis of the Adult-Child conflict is revealed. This is the story the Adults do not want you to hear.

It's the Delightful Children From Down The Lane's birthday again, and that means it's time once again for the Kids Next Door to make off with their fantastic cake! But when the plan to egg the Delightfuls to submission goes afowl, the Kids must decide whether the cake is really worth it.

The Kids Next Door have the misfortune of swapping the Toilenator to Mr. Boss with the unlucky Numbuh 13, who informs the operatives of the adult villains' plans for a macaroni dinner by ransacking a museum of macaroni art.

Numbuh 4 is forced to choose between helping the KND battle the villainous Soccer Mom or engaging at his new gig as a matador in the Bully Fights.

The Delightful Children kidnap the team's classmate, nerdy, spit-talking ""Leaky"" Leona, and force her to lead them to the dark underbellies of the school. Alerted by Numbuh 5, the team follows them, and find themselves in an ancient school, laden with deadly booby traps. Avoiding them all, the team finds Leona, strangely aged to an old woman, who leads them to the mythical Fountain of Youth! The KND are amazed at the prospect of remaining ten years old forever, but the Delightful Children desire nothing less than to destroy the Fountain, claiming that the goal of all children should be to grow up. Can the Kids Next door save the supernatural spring? And what strange secret is ""Leaky"" Leona hiding?

Feeling that Numbuh 1 must take a day off, the team force him to go to the beach, telling him to have fun or else. Nigel makes an honest attempt - until a crab swipes his swim trunks! After suffering a great amount of public embarrassment, 1 makes his way back to the Treehouse... and minutes later, walks out of his room to tell his terrified team that he's resigning from the Kids Next Door! After he leaves, the purpose becomes quite clear... an envelope is found in his room from the Delightful Children, with a picture of his tush and a note saying ""Leave your team behind or we'll put your behind in the school yearbook."" Now Numbuh 1 is heading for Delightful Manor, where the evil peeping toms desire to make him one of them! Can the team save their leader from the sadistic shutterbugs?!