A group of children are investigating a chain of mysterious events during the seventies.
A red haired Petra is not your ordinary girl - in addition to her regular "girly" interests she's also a goalie in boys football team.
Even a strict and not very popular teacher can achieve extraordinary popularity with his pupils. When their favourite teacher breaks his leg just before a bicycle trip, he is replaced by his strict colleague. Although his involuntary charges are not enthusiastic at first, they eventually become convinced that it is not good to immediately reject a person just because one does not get along with him at first...
