The remaining three eat breakfast. The storm is gone, and they feel as though a nightmare has passed. Lombard begins to make plans to signal the mainland. They discuss Armstrong’s mysterious disappearance, and Lombard and Blore get into an argument: Blore finds it sinister that Lombard has his revolver again, but Lombard refuses to give it up. Blore suggests that Lombard may be the killer, and Lombard asks why he wouldn’t simply shoot Blore if he were the murderer. Vera scolds them for being distracted. She points out the verse in the rhyme that applies to Armstrong’s death: “A red herring swallowed one and then there were three.” A “red herring” is a term for a false lead or a decoy, and she thinks that Armstrong is not really dead and that he has tricked them somehow. Blore points out that the next line is about a zoo, which the murderer will have a difficult time enacting on their island, but Vera says impatiently that they are turning into animals.
Vera, Blore, and Lombard spend the morning on the cliffs trying to signal a distress message to the coast using a mirror, but they get no answer. They decide to stay outside to avoid the danger of the house, but eventually Blore wants to fetch something to eat. He is nervous about going alone, but Lombard refuses to lend him the revolver. When Blore is gone, Lombard tries to convince Vera that Blore is probably the killer. Vera says she thinks Armstrong must still be alive. She then suggests that the killer could be alien or supernatural. Lombard thinks this mention of the supernatural indicates Vera’s troubled conscience and asks her if she did kill Cyril. She vehemently denies it at first, but when he asks if a man was involved, she feels exhausted and admits that there was a man involved. They hear a faint crash from the house and go to investigate. Blore has been crushed by something thrown from Vera’s window: the bear-shaped marble clock that stood on her mantle. Thinking that Armstrong must be inside the house somewhere, the two go to wait for help. On their way to the cliffs, they see something on the beach below. They climb down to look and there find Armstrong’s body.
Vera and Lombard, dazed, stand over Armstrong’s body. Vera looks at Lombard and sees his wolflike face and sharp teeth. Lombard nastily says that the end has come. Vera suggests they move the body above the water line. Lombard sneers at her, but agrees. When they are finished, Lombard realizes something is wrong and wheels around to find Vera pointing his revolver at him. She has picked it from his pocket. He decides to gamble and lunges at her; she automatically pulls the trigger and Lombard falls to the ground, shot through the heart.
Vera feels an enormous wave of relief and severe exhaustion. She heads back to the house to get some sleep before help arrives. As she enters the house, she sees the three statues on the table. She breaks two of them and picks the third up, trying to remember the last line of the poem. She thinks it is “He got married and then there were none.” She begins to think of Hugo, the man she loved but lost as a result of Cyril’s drowning. At the top of the stairs she drops the revolver without noticing what she does. She feels sure that Hugo is waiting for her upstairs. When she opens the door of her bedroom, she sees a noose hanging from the black hook that previously held the seaweed. She sees that Hugo wants her to hang herself, and then she remembers the real last line of the poem: “He went and hanged himself and then there were none.” Without a second thought she puts her head in the noose and kicks away the chair.
The apparent end of the novel is calculated to leave us in a state of utter confusion. Since we have no idea that Wargrave is still alive, it seems that the murderer must either be Vera or Lombard. Yet we are left with no idea how either one could possibly have killed Blore, whose death takes place while the two are together by the sea, or, for that matter, how either could have killed Armstrong, since both of them are asleep in the house when he goes outside. Additionally, there is the matter of the Indian figurines, which continue to disappear like clockwork even when the house is apparently empty.
When all of these facts are considered, the only possible conclusion is the correct one—namely, that someone else is still alive on the island. Yet all the evidence that the novel has provided thus far suggests that this is impossible. In their final confrontation, both Vera and Lombard accept it as a given that they are alone on Indian Island, and each assumes that the other is the killer. In a way, their behavior is irrational, since they should know that neither one of them could possibly have killed Blore. This kind of perfect rationality, however, may be too much to ask of a pair of human beings who have endured such a strange and terrible sequence of events. In the end, both Lombard and Vera accept the logic of the poem, and they assume that everyone who seems to have died really is dead. A careful examination of the evidence is beyond their capabilities.