Mama's Proefkonijn plot
Steven finds out through his classmate Mariska that his mother uses laboratory animals in her research into eye disorders. After his shocking discovery, he starts to look at his mother with different eyes. He turns away from her and seeks comfort from his father in the countryside. Finally, he decides to take a rigorous act. Together with Mariska, he breaks into his mother's laboratory and releases all the laboratory animals. When he learns the next day that the freed animals will not survive outside their cages, the magnitude of his action dawns on him.