End of the 1970s. 29-year-old Petra Grust is enthusiastic about her new job as a biology teacher at the Odenwald School (OSO), which is a legendary flagship institution of progressive education. She honors the confidence of the charismatic and famous headmaster Simon Pistorius. But the boarding school life is irritating. Students and teachers of both sexes use the same showers, young students drink alcohol and smoke, and a colleague even has an affair with an underage student.