Kim has to fit both foiling Drakken's plan to use stolen nano-explosive technology and detention into her life after Ron inadvertently causes her to fail substitute teacher Mr. Barkin's "three strikes" tardy policy.
She discovers that the bracelet grows every time she lies, leading to embarrassment when she tries to get out of a series of engagements to attend a Halloween party with Josh Mankey.
Naco royalties suddenly make Ron a tremendously wealthy multimillionaire, then he proceeds to squander his newfound fortune on a posse of fake friends and spending binges.
Meanwhile, when handsome new student Eric comes between Kim and Ron's close friendship, they are forced at long last to examine their true feelings for each other and the nature of their relationship.
When Kim's usual mission attire is no longer available for purchase at Club Banana, she tries to look for a new one, all while worrying about college admissions and Drakken's latest scheme to reform the continents into the next Pangaea.
Ron has his hands full when he has to care for both a sack of flour (as part of a school project) and his new adopted baby sister Hana, not to mention help track down Monkey Fist, who is in search of three stone keys that will lead him to a secret weapon.
Soon, they are called by Master Sensei and Yori, who ask them to help stop Monkey Fist, who has found a new ally in Yono the Destroyer as he continues his search for the secret weapon.
While Ron worries that graduation means the end of his romantic relationship with Kim, a vengeful Warmonga returns with her battle-mate, Warhawk the Conqueror, to invade Earth.
On graduation day, Kim is abducted along with Drakken by the alien invaders, and must work alongside him, Ron, and Shego to foil the Lorwardians' planetary assault.