A sudden and unexpected knock on the door of the staff room at a municipal grammar school one Friday afternoon. Surely no pupil would ever dare do that? No, in fact it's an ambitious father who is fighting for his son to be allowed to take the Abitur exams - and is even prepared to go to extremes to achieve his goal. Those six teachers still in school will now get to see what he is prepared to do the hard way: initially, they all feel themselves superior to the desperate father, but soon discover that the situation is getting more and more out of control. After some unexpected twists and embarrassing revelations, veritable abysses open up for everyone involved.