A small Czech city, winter. Eight-year-old Petrik is excluded from his hockey team before the important annual ice-hockey match with a neighboring town. As the coach says, he has a lack of skills, speed and most of all - courage. Peter’s best friend Bara suggests him to continue self-trainings on a frozen lake on the outskirts of the town. After struggling with his fears, Petrik does so.
At the same time a greedy pharmacist Dr. Studna decides to launch the production of rejuvenating cosmetics made of a clay from the local lake. It gives him a lot of profit.
At his training Petrik meets the talking carp called Kupryan. The Carp tells the boy that fish also play the similar game on their side of the ice and offers Petrik his coaching aid. They start doing their trainings together. Gradually Petrik and Kupryan become good friends. Kupryan shares with Petrik also his wisdom. (excerpt)