Lollypop lady and former chief inspector Pam Travers is taking things far too seriously at the school crossing again. Year 9 are confused when Miss Crank actually does give up pranking, preferring instead to teach history at last. Meanwhile, the whole school is thrown into chaos when all the toilets get blocked, leaving everyone desperate for the loo. It all seems to have been caused by the same person, which leads head teacher Mr Goldman on a hunt to find the phantom toilet blocker.