High school professor of chemistry and physics Samo Demšar is an excellent teacher and always on the side of the students. He is an eternal youth in personality and still a teenager at heart, which is why he understands his students so easily. But he often finds himself in trouble, also because women like him at least as much as they like him. At first, it seems that the exception will be the new professor at the high school, the attractive Slovene scholar Klavdija Jaklič, who is very happy to participate in Sam's solution to the various problems faced by the growing students. In the first episode, Samo accidentally reveals to student Roku that his parents adopted him.

The students have a new school year ahead of them, and Samo, the professor of chemistry and physics, who always stands by the students, even if it sometimes doesn't seem like it at first glance, also returns to school after the holidays. Klavdija, the professor of Slovenian, also returns, and both Sam and Klavdija are not quite sure what waters their love will sail into. Quite a few new students come to the school, including Niko, who is on parole. The new school year also brings a new professor, Barbara, who develops a romantic relationship with Želet, while Principal Vojc's biggest challenge is dealing with personal problems.