A hairdresser Gerda has an affair with Dr Nikodimov, a married man past his prime. Savarinova has had her hair done by Gerda in fashionable style. She is ill at ease at a family party. Her sister Mina has been the cause of her anxiety, because the young scientist Belokozhov prefers young and unaffected Mina. They go out to the park and have fun by themselves. Meanwhile, Nikodimov goes to see Gerda in her flat. She tells him what has been preying on her mind during their liaison. Nikodimov's wife comes there but he turns her away. He tells Gerda that he will move in with her for good. Heartbroken, the girl turns him away. Nikodimov goes to the hospital. In his office, he takes out an ampule of cyanide and drains it with a resolute gesture. Mina and Belokozhov discuss love in the park. It starts raining. Laughing, a boy and a girl walk towards the dawn.