The story is set on an island in the middle of the river Mura, where Jožef and Ana, an old couple, can bear the solitude of their life, because of their affection and their compassion for the blind Katica. The girl is living with them because her mother and stepfather work abroad and only visit her now and then. Katica sings charmingly, pleasing everybody who hears her. One day Peter, the grandson of the old couple, who is a bandit on the run from the police, comes to the house. Katica falls in love with him, her mother Marta is caught by passion. Peter is causing a lot of troubles and he is chased by the police all the time. Katica saves him with her singing in the middle of the marsh and unable to find her way out, drowns.