A young boy from the city comes to the forester Januszko, a friend of his grandfather from the war and partisans. On the spot, he meets people who amaze him. They bear the names of the heroes of the novel "Summer of Forest People" by Maria Rodziewczówna, which they readily read and love nature very much. Under their guidance, the boy gets to know the local nature and makes friends with them. He also meets a girl named Justyna.
