The title refers to the Feuerzangenbowle punch consumed by a group of gentlemen in the opening scene.  While exchanging nostalgic stories about their schooldays, the successful young writer Dr. Johannes Pfeiffer realizes he missed out on something because he was taught at home and never attended school.  He decides to make up for it by masquerading as a student at a small town high school and quickly gains a reputation as a prankster.  Together with his classmates, he torments his professors Crey, Bömmel and Headmaster Knauer with adolescent mischief.  His girlfriend Marion unsuccessfully tries to persuade him to give up his foolish charade.  Eventually, he falls in love with the headmaster’s daughter and discloses his identity after provoking the teachers into expelling him from school. 

Wenn beim Herrenabend seine Freunde Anekdoten aus der Schulzeit austauschen, kann der bekannte Schriftsteller Dr. Johannes Pfeiffer nicht mitreden. Er ist auf dem väterlichen Gut von einem Privatlehrer unterrichtet worden. Um seine verlorene Jugend nachzuholen, verwandelt sich Dr. Johannes Pfeiffer in den Pennäler Hans Pfeiffer und besucht das Kleinstadtgymnasium zu Badenburg. Mit immer tollkühneren Streichen treibt er die versammelte Lehrerschaft in den Wahnsinn – und findet nebenbei die Frau fürs Leben: Eva, die Tochter des Schuldirektors.