Most of her colleagues take Mária, the new teacher to be a communist party-worker, only Irma and the drawing teacher Zoli treat her kindly. Mária starts working with great enthusiasm, and her class learns to love her in a short time.

The head of the nunnery is dying, and the members are divided in two groups as the election of the new head approaches. Led by Virginia, the younger nuns stand up for changing the strict religious dogmas and would like a modern school with genuine science, a bathroom to be built, and a freer spirit. Their candidate is sister Magdolna, who went to secular universities, too. The seminarists, led by Király Erzsi, also rebel against the older nuns' strict discipline and the depressed atmosphere of the institution. However, Magdolna does not want to stay involved in the fight because she is deterred by Virginia's sinful attraction towards her and the tools Virginia is using to gain victory at any price.