Mrs. Mooney, separated from her husband, a butcher who descended into alcoholism, runs a boarding house for working men. Her daughter Polly entertains the boarders by singing and flirting with them. Mrs. Mooney learns that her daughter is having an affair with Mr. Doran, a man in his mid-thirties who has worked in a Catholic wine-merchant’s office for many years. On Sunday nights, Polly would sing with the various guests in the boarding house. It is noted that she sings "I'm a naughty girl," which Zack Bowen suggests foreshadows her affair with Mr. Doran. Mrs. Mooney bides her time before she intervenes, strongly implying that she is deliberately trying to trap Mr. Doran. After much background, the climax of the story commences on a warm Sunday morning. Mrs. Mooney intends to talk to Mr. Doran and demand that he marry Polly or risk open disclosure. The narration then shifts to Doran’s point-of-view as he nervously contemplates losing his job due to the affair and bemoans the girl’s lower-class background and vulgarities of speech. After Polly enters in an agitated state, we learn through Doran’s memories that she initiated the relationship. After Doran leaves the room, Polly seems content, suggesting that she was putting on a show of anguish for his sake. The story closes with Mrs. Mooney calling Polly down so that Mr. Doran can speak to her.