For the first time in years, the new academic year in the honourable Chavale Lyceum begins free of worries, as the racy and noisy batch of mischievous students has finally graduated, free to become someone else's problem. However, things will take an unexpected turn, when Bilias and his band of misfits decide to retake the final year to finish school without fear or favour, much to the dismay of their poor instructors. Perhaps the arrival of a new Chemistry professor and an improbable kindergarten teacher will help to tame the class. But is that even possible?