Kriszta sings in the Alfa-Beta-a beat band, which her father doesn't particularly approve of. But in order to make music meaningful, Géza, guided by a newspaper article, takes the entire band to a rural TSZ stable, so that the cows will produce more milk with the music playing. However, the cows and bulls go wild and not only break the stable, but also the instruments, speakers, and amplifier. Needing immediate help, Géza turns to MZ/X, Öcsi, again. However, the sound amplifier device from the 30th century, delivered by light mail, is too powerful.