Lamput is hiding in a school, and the only way for the Docs to get him is to anti-age zap themselves back into childhood. After stalking him in the corridors and unsuccessfully evading detention slips from the Headteacher, they find themselves in class. Skinny is rather happy to be back, but Specs doesn't like tests or art or chemistry or anything that distracts him from his true objective. Each time they almost get him, Lamput is saved by the bell (and even becomes the bell), and it's a race against home time to see if they can get Lamput before the Headteacher gets them.