Donny (from “Horn, Sweet Horn”) stays with the girls for a week as part of a student exchange program, but at school, he starts hanging out with a girl named Chelsea, much to Bubbles’ jealousy. But after Bubbles bends Donny’s spoon in front of him and he runs out of the house, the girls find out that Chelsea lives in a volcano, which is actually Mojo Jojo’s lair. They go there and see that Chelsea is actually a robot, engaging each other into a fight, and also see that Donny’s magic is being drained for Mojo’s death ray.