Shaggy & Scooby-Doo Get a Clue! Season 2 Episode 10 Don't Get a Big Head ( Air Date 2008-02-16 ) Genre Animation, Comedy, Family, Kids, Mystery category. Overview "Dr. Phibes, tired of being outsmarted by our heroes, revises his nano formula to increase his IQ. It also inflates his head. Now, Shaggy and Scooby must stop him from releasing a gas that will drastically lower the world's intelligence.".