Last Updated September 5, 2023.
Ellie Dunn, a young woman, arrives at the home of Captain Shotover and his daughter, Mrs. Hesione Hushabye—having been invited by Mrs. Hushabye. However, no one is there to greet her, and she sits and reads while she waits for someone to notice her. She meets Nurse Guinness and the Captain just before Lady Utterword, the Captain's younger daughter, arrives home after a very long absence. Utterword is followed by Mazzini Dunn, Ellie's father; Randall, Utterword's brother-in-law (who is in love with her); and Boss Mangan, Ellie's betrothed.
Hesione wants to prevent Ellie from marrying Mangan, who Ellie has settled on despite her lack of affection for him. Ellie tells Hesione that she fell in love with a man named Marcus Darnley, but it turns out that Marcus is really Hector Hushabye (Hesione's husband), who makes a habit of lying about his identity in order to deceive women. This breaks Ellie's heart, but Hector soon gets his own heart broken by his sister-in-law, Lady Utterword, with whom he falls in love practically at first sight.
While Mangan is in a trance-like sleep, Hesione and Ellie have a conversation about him that includes condemnations and unflattering descriptions of him (of which he can hear every word). It turns out that Ellie is only marrying him for his money, knowing that this is the best a woman in her position can do.
In the course of the evening, Mangan eventually confesses to ruining Ellie's father; he had loaned her father money in order to help Mr. Dunn set up a business. When this venture failed, he offered to help him again by buying the business and offering Mr. Dunn a position. However, Mangan reveals that he knew that Mr. Dunn would ruin his business and had only offered the loan in order to buy the business at a much cheaper price once it failed. Magnan thus reveals that these actions, which at first seemed kind and generous, were actually unscrupulous.
In the course of the evening, a robber suddenly breaks into the house to steal Lady Utterword's jewels, but he is shot by Mr. Dunn. He turns out to be a former cohort of Captain Shotover named Billy Dunn (who the Captain originally thought was Ellie's father, but he is no relation). Billy then proceeds to extort the family; using the threat of a public scandal to intimidate the wealthy family, he gets them to pay him money by threatening to turn himself into the authorities. It is revealed that he has never actually stolen anything and that he has repeatedly used this technique to capitalize on the conventions of upper-class decorum (i.e., their fervent desire to avoid scandal).
Explosions are soon heard when wartime airplanes drop bombs from overhead, and Billy and Mangan run from the house and hide in a pit, unaware that this is where the Captain keeps dynamite hidden (which he uses to conduct experiments). Despite the fact that Hector turned all the lights in the house on—disobeying the police and all common sense—the house and everyone in it survive, while a bomb is dropped on the gravel pit, killing Billy and Mangan. Ellie then marries the Captain (a man much older than her) in secret, and she and Hesione laugh about the bombs, comparing them to Beethoven's music, hoping for more excitement tomorrow.
Ultimately, the upper class, which includes Ellie by the end of the play, are portrayed with a glaring lack of empathy. In the end, their lack of concern for the gravity of the deaths of the two men and their callous (and perplexing) fixation on the excitement caused by the bombs reveal them to be frivolous and unscrupulous as well as to have a misalignment of priorities.