Research institute director Maska and his family are having supper in his plush villa. The arrival of an unexpected visitor pleases the director's son Otakar - it is his former schoolmate and friend Lumír Brabec. Brabec has broken off relations with his family and left his job and the town where he used to live. Otakar is delighted to see him and employs him in the brick-works where he is one of the managers. He even puts him up in the villa. Otakar's attractive sister Lída is just finishing university and she takes a fancy to the handsome Lumír. Although she has an official suitor in the shape of Dr Polák, she prefers Lumír and the two become lovers.