White Nights tells of four nights and one morning in the life of a man of twenty-six, unnamed, who lives alone in St. Petersburg and by reverie: on the embankment of a canal he meets a weeping girl, Nastenka, falls in love with her against the condition she imposed, is accepted for a few hours, and loses her when the man she had been waiting for a year returns.
On the First Night, at the start of summer, the city leaves for the country houses and the Dreamer feels abandoned by people who do not even know him. On his way home after ten, he rescues a girl from a drunkard with the walking stick he carries, asks to see her again, and hears the condition: that he not fall in love. On the Second Night, he paints the portrait of the Petersburg dreamer, who clings to his corner like a snail, and she tells her story: orphaned, pinned to the dress of her blind grandmother with a pin, she fell in love with the lodger of the mezzanine, who left for Moscow promising to return. The year has passed, he has been in the city for three days and has not appeared, and the Dreamer carries to her acquaintances, who will get it to the lodger, a letter she had already written.
On the Third Night, she waits happily and says she likes the Dreamer because he did not fall in love. On the Fourth, with no reply, she weeps; he declares his love, she asks herself whether her love for the other was an illusion of the imagination, and offers him her hand. As they make plans, a young man passes and calls her by name: it is the lodger. She runs to him, comes back to kiss the Dreamer, and goes away with the other.
In the Morning, a letter from her arrives announcing the wedding and asking that he be a friend and brother to her forever. The Dreamer finds himself alone in the same room fifteen years from now, blesses Nastenka for the minute of happiness she gave him, and ends by asking whether a minute like that is too little for a whole life.