Warm summer night. The eve of John the Baptist feast. According to tradition, girls throw garlands of flowers onto the river to predict their future. The most beautiful among them is Lileya, and all young men are charmed by her. She loves Stepan, her childhood friend, and their love is mutual. Lileya and Stepan ask the Prince’s permission for their engagement. At first, the Prince agrees, but then, seeing the girl’s beauty, he decides to part the beloved couple; he orders to bring the girl to his castle and take Stepan as a servant. However, the community decides to send Stepan to Zaporozhian Sich and to protect Lileya from the Prince.

Prince’s soldiers search for Lileya. Exhausted, Lileya is on the bank ok the lake. Tired and lonely, she is found by gipsies. They take care of the girl and help her to escape the soldiers. Lileya falls asleep and dreams a strange dream: Stepan is surrounded by dancing mermaids. But suddenly, she awakes.

Blind folk singers – the kobzars – are approaching the lake. Stepan is among them. On his way to Zaporozhian Sich, he was caught and blinded by the Prince’s soldiers. The Prince appears and wants to kill helpless Stepan, but Lileya protects her beloved. People come to help the young couple. The peasants kill the dishonourable Prince, and the blind Stepan calls to fight for freedom and happiness.