Poor musician Alojzy Kędziorek is in love with Sagankiewicz's daughter Renata, who is reciprocated, but her family wants to marry her off to the wealthy butcher Baleron. Hipek, Alojzy's friend, sells his song to the theater director. The song becomes a huge hit. Alojzy is mistakenly locked up in a newly opened psychiatric hospital. He manages to escape. He goes to the theater where his song is being sung. He receives thunderous applause and an order for new songs. Renata's family agrees to her marriage to Kędziorek.