In the movie, Kim Possible and Ron Stoppable are both juniors in high school and are hired by Dr. Drakken to steal a powerful top-secret device called the "Synthodrone". Throughout the movie, Drakken attempts to use this device to clone himself and take over the world.
Meanwhile, at Middleton High School, a new student named Eric arrives and catches the eye of both Kim and Ron. Ron becomes jealous of Eric and starts to realize his feelings for Kim go beyond just friendship.
As the team works to stop Drakken, they face challenges such as fighting their own clones which Drakken created with the Synthodrone, battling robotic monsters, and uncovering the true identity of a mysterious villain known as Shego.
Throughout the movie, Ron struggles with his feelings for Kim and ultimately confesses his love to her, leading to a sweet moment between the two friends. In the end, Kim and Ron are able to save the world from Drakken's evil plot and Ron finally gets his revenge on Bueno Nacho.