Justine Flanner is a highly intelligent Middleton High School student. She is well-known for her stellar performances at science fairs.
Justine made multiple breakthroughs in particle physics, most of them apparently in eighth grade. Mr. Barkin assigned Justine to be Kim Possible's science project partner. Excited at the thought of having such a brilliant partner, Kim was eager to help out. Justine, however, made it very clear that she intended to do all of the work alone. A mission to stop a rampaging "dino-thing" created by Dr. Drakken and DNAmy presented Kim with a perfect chance to test out Justine's science project: a kinematic continuum disruptor. Using the Kimmunicator's batteries as a power source, the disruptor opened a wormhole that dragged the creature inside, effectively saving Middleton. Unfortunately, Mr. Barkin did not believe the machine could do what Justine claimed it could, and activated it in the middle of the school, unleashing the dinosaur once again.
Justine is very aware of just how smart she is, and as a result, is also aware how much smarter she is than most other high school students. Therefore, she does not expect many people her age to understand or appreciate her work in science. Justine tends to be slightly conceited and considers herself superior because of her intelligence, although since even established, experienced scientists are humbled by her work, Justine's opinion of herself is not exactly without merit.
Justine is a very intelligent and gifted scientist. As her reputation more than impresses rocket scientist Professor Allenford, Justine is most likely well on her way to becoming yet another of Middleton's resident geniuses.
- In addition to holding both a bachelor's degree and PhD in neuroscience in real life, Justine's voice actress also stars on The Big Bang Theory as Sheldon Cooper's girlfriend, Doctor Amy Farrah Fowler, a neurobiologist whose test subjects are mainly monkeys.