Summary: After a successfull mission against the Ice Cream Men as they were making a new flavour to brain wash kids world wide, Sector V here a message to go to Moonbase Headquarters. once there they find out that Numbuh 362 found out that many kids have "a virus that makes them, weird" and a mutagen that turns kids and adults into monsters!!! Telling them to guard them with their lives she brings two operatives from Sector Y to them, Numbuh 626 (who has this "Virus") and Numbuh 627 (Good friends of Sector V)! Numbuh 5 (who hadn't seen him in a while and forgot a bit about him) immediantly recognised Numbuh 626 because he knows her because she told him Numbuh 11 betrayed the Kids Next Door. Scott (Numbuh 626's real name) was as excited as ever but still thinking about Numbuh 624 (Natasha) as she was decomissioned. Mr. Boss, Knightbrace and Mr. Wink and Mr. Fibb find out about the KND coming over and warns "Exectrifier" the head of the industries and more powerfull than him!!! Just then the Toilenator arrives (who comes as an unexpected guest) Exectrifier puts Toilenator in a chamber and zaps it with the Toilenator becoming a MONSTER!!! Sector V and the two operatives from Sector Y go to the Evil Industries in Cardiff and the monster Toilenator and he procides to attack them! Scott, still thinking about Numbuh 624 but quickly shakes it off, he then uses the B.O.O.M.B.U.S.T.E.R. and fires at Toilenator. But Toilenator (With the Toilenators personality and under Exectrifier's orders) breaks open a door that reads "The TEEN VIRUS"! Quickly Numbuhs 626 and 627 put on their Birthday Suit armor on while the others were too late with a BOOM the two operatives shut the door (by sealing it with duck tape) and then see Sector V grow taller untill... THEY WERE TEENAGERS!!! Scott panicingly asks himself why he didn't stop the monster Toilenator until the now teenaged Sector V kindly tell him it wasn't his fault. Scott (who was touched by what they said) whispers to Christopher (Numbuh 627's real name) and says that "Their lost childhood will not be in vain!" Exectrifier was pleased with the results until Scott, Christopher and Sector V burst through the door and demand the Mutagen and Antidote. Exectrifier doesn't see them as a threat and orders the Teen Ninjas to attack, however, Cree was happy and touched that Numbuh 5 was a teenager and states to him that "Why don't we chase Sector Y!?" Cree sees Scott & Christopher and attacks them (after deciding to make them her's and to make their weapons her own "trophies") Cree chases Scott and Christopher all down the Evil Adult Industries, but Scott and Christopher got pulled away from Cree and her B.R.A into a dark space inside one of the rooms for storage, Both of them find out that the one who saved them is the supposedly decomissioned Numbuh 624 herself!
13 years old she tells them It's been too long as they point that they saw her get decomissioned, she said "You two (Scott and Christopher) thought I was gone, but It's a long story" and tells them she's with the T.N.D. as a spy for the K.N.D. all because of them! Feeling honoured Scott and Christopher promises to do his best in this mission and all others!!! Unfortunetely the noise from that promise attracts Cree and starts blasting down the door, telling them farewell, Numbuh 624 (If you still consider her apart of the K.N.D.) stalls Cree with their usual gossip (no effence) and Scott and Christopher races down back to Sector V and Exectrifier.
Before even getting a chance to blast Exectrifier, he once again zaps Toilenator and then he rampages and gets really angry and calls Sector V jerks and claim that now he should rule Which everyone laughed at (as they don't think he's good enough)! This angers the monster Toilenator even more Numbuh 4 charges but trips over his new teenaged feet, much to Scott's amusment. Exectrifier then threatens to use the monster mutagen on Sector V unless Scott and Christopher upgrade his Shock Suit (what he uses to turn Toilenator into a monster) Christopher tampers with the suit without Exectrifier knowing and gives it to him he brakes his promise and tells them he'll turn them into adults then turn Sector Y in to Father for money! But as he blasts it the teenage Sector V turned back into kids!!! Toilenator brakes is control and laughs at Exectrifier as he zaps him again, this time turning him back to normal! Exectrifier realises he ws tricked while Scott and Christopher are heaped with praises and hugs from Sector V!!!! Scott then uses the B.O.O.M.B.U.S.T.E.R. and bring Exectrifier crashing to the ground. The kids next door high-Fives a job well done Numbuh 5 was okay with being a teen in a few years time because of what happend to Cree 3 years ago. Scott calls out to Sector V and that he found "Yipper #100" just in time for Numbuhs 86 and 362 come and congradulate Scott on their mission and when he gets back to Sector Y a reward will be there!!! Overjoyed Scott lets Numbuh 3 listen to the Rainbow Monkey song on his B.O.O.M.B.U.S.T.E.R. making Numbuh 4 growl at him. Numbuh 86 has Exectrifier and the other villans in her ship and with 362, leaves, Numbuh 5 finally tells the others that Asperger Syndrome is what Scott was born with!!!
- This is the third episode to have the name of the central KND operative: first being Operation C.H.A.D. and the second, Operation M.A.U.R.I.C.E.
- This is the second time Hank (the teenaged Numbuh 2) appears first being in Operation: K.I.S.S. however this transformation lasted longer as Numbuh 2 was effected by the TEEN Virus along with Sector V.