Petr Rynes (Svatopluk Matyás) is celebrating his forty-fifth birthday in the company of his friends. He is happy with his wife, and his abilities at work have been rewarded with the medal For Outstanding Work. But a few short seconds are enough to change his life when he makes the ill-judged decision to take his car to bring a friend's wife to the celebration, and hits a pedestrian on the way. He has of course been drinking at the party and is consequently sentenced to sixteen months in prison. Being in jail is not an easy thing for a honorable communist. He soon gets into conflict with several violent inmates, who think they can break his spirit by violence.