Ulla is a sensitive and principled 10th-grader in a small East German town. When Winfried falls in love with her, he adopts her passion for protecting the environment. Ulla tries to stop illegal trout farm and gets her classmates involved.

15-year-old Ulla lives with her mother and her mother's boyfriend Erich in a small town in the GDR. The old building has no electricity, and pigeon droppings cause vermin and skin infections. After a swimming trip with her friend Birgit, she meets Winfried. He is the son of an influential general director and has all the things that most young people only dream of: a computer, a games console, a Walkman, a motorcycle. The two fall in love. On an excursion with their biology class, the students discover that a dacha is being built in the middle of a nature reserve. They soon find out that the small stream that flows there is also to be dammed for trout farming. Everything seems to have been approved by the mayor himself. Ulla and her friends do not want to accept this and organize a protest. But when it turns out that the builder is Winfried's father himself, who wants to fulfill his dream of peace and quiet here, Ulla and Winfried's relationship threatens to fail.