Mr. Owen could only come to the island in one way. It is perfectly clear. Mr. Owen is one of us.
Blore, Lombard, and Armstrong become argumentative. Blore suggests that Armstrong gave Mrs. Rogers an overdose of sleeping medication either by accident or on purpose. Lombard tells Blore not to be offensive, and Blore demands to know why Lombard carries a gun. Lombard explains that he was hired to do a job by Isaac Morris, who implied that he might find trouble of some sort on the island. The bell rings, announcing lunch. Everyone troops in for the midday meal except for Macarthur, whom Armstrong goes to fetch. Rogers serves a makeshift lunch of cold ham and tongue along with a few other items, anxiously expressing his hope that the food will satisfy the guests. People make small talk about the approaching storm and then hear the doctor returning at a run. He bursts into the dining room, and Vera immediately surmises aloud that Macarthur is dead. Armstrong confirms this fear, stating that Macarthur was killed by a blow to the head. Blore and Armstrong retrieve Macarthur’s body, and the storm breaks as they bear the corpse into the house and place it in Macarthur’s room. Vera and Rogers notice that only seven statues remain on the dining-room table.
Everyone except Rogers gathers in the drawing room, and Wargrave takes charge of the meeting. He says he has come to the conclusion that the murderer is one of the guests. The others, except for Vera, agree with this theory. He then asks if anyone can be cleared of suspicion. After some initial objections, including discussions of whether women and professional men can possibly be suspected of such crimes, it is agreed that they must proceed as if any of them could be the murderer. The guests then review their movements of the past two days to see if anyone’s actions made it logistically impossible that he or she committed all three murders. No one has a foolproof alibi. Wargrave warns everyone to be on his or her guard, and dismisses them as if adjourning a court.
Vera and Lombard talk in the living room. They agree that they do not suspect one another. Lombard remarks that Vera seems very levelheaded for a woman. He then tells her that he suspects Wargrave; perhaps, Lombard suggests, years of playing God as a judge have driven him mad and made him want to be both judge and executioner. Vera says she suspects Armstrong, because two deaths by poison sounds like a doctor’s handiwork. She suggests that he might have killed Macarthur when he went down to fetch him for lunch. She also points out that since Armstrong is the only member of the group with medical knowledge, he can say what he likes about the manner of death and no one can contradict him.
Rogers, polishing the silver, asks Blore if he has any suspicions. Blore says he suspects someone, but he will not say whom. Meanwhile, Wargrave and Armstrong talk. Wargrave strikes Armstrong as eager to hold on to his life. Armstrong worries that they will all be murdered in their beds, and Wargrave thinks to himself that Armstrong can think only in clichés and that he has a “thoroughly commonplace mind.” Wargrave then says that while he has no evidence that would stand up in a court of law, he thinks he knows the identity of the murderer.
Emily sits in her room, writing in her diary. She begins to feel groggy and writes in a shaky hand that the murderer is Beatrice Taylor (the pregnant maid she once employed who killed herself). She snaps to her senses and cannot believe she could have written such a thing. She thinks that she must be going mad.
Later that afternoon, everyone gathers in the drawing room. The normalcy of teatime makes them relax a bit. Rogers rushes in to announce that a bathroom curtain made of scarlet oilsilk has gone missing. No one knows what this absence means, but everyone feels nervous again. The guests eat a dinner consisting mostly of canned food. They retire to bed soon after eating, locking their doors behind them. Only Rogers remains downstairs. Before he goes to bed, he locks the dining-room door so that no one can remove any of the remaining Indian figures during the night.