Dr. Armstrong jumps up to check Marston's pulse and proclaims him dead. No one can believe it because Anthony looked like such a healthy, godlike man. Armstrong smells Anthony's breath and states that he has been poisoned. He then smells the bottle of whisky and the soda and says they are both un-poisoned, so Marston must have put the poison in his own glass. No one can believe it but they can't think of a better explanation. Miss Brent suggests that they should all go to bed.
The shift from healthy life to cold death is so quick that no one can believe it. Although Marston has just been poisoned no one tries to figure out who did it. It seems unlikely, given his personality, but they all believe it must have been suicide. They don't believe that anyone would murder Marston without knowing him and without having good reason.
Mr. Rogers checks on his wife and says that she is sleeping well. Everyone goes upstairs, says goodnight and locks their doors
They still maintain civilized practices, but they are starting to fade.
Wargrave, alone in his room, thinks of Seton. He remembers how much he enjoyed the case: Seton's lawyer had made a great final speech but then Wargrave summed it up and sealed Seton's execution. Downstairs, Rogers notices that one of the Soldiers on the dining-room table has gone missing.
A soldier is taken away because one of the guests has been killed, a pattern that will be repeated throughout the novel. We learn that Wargrave feels no guilt.
General Macarthur cannot fall asleep because he keeps thinking of Richmond. Macarthur had loved his wife, Leslie, and was happy when she became friends with Richmond. He was devastated when he found out, from a misaddressed love letter, that Leslie was having an affair with Richmond. He was so angry that he deliberately sent Richmond to his death. Leslie never said anything and died three or four years later. Macarthur worried that other people in the Army had known; he never had any real knowledge that anyone did, but he began avoiding his fellow veterans.
Macarthur's life, since he sent Richmond to his death, has been plagued with guilt. Christie slowly reveals the reason that each character committed murder. They are all ambiguously guilty. For example, Macarthur did not actively kill Richmond. This is why he has been able to conceal it, and has not been punished, for so many years.
Macarthur wonders whether anyone believed the accusation and then thinks that it is impossible that the two women on the Island had committed murder. He wonders when they will all leave and then thinks of all the troubles and worries that await him on the mainland. He realizes then that he doesn't want to leave the island.
Macarthur realizes that his guilt has become too burdensome. He does not even want to live anymore. Almost every character has made the sacrifice of living with guilt to avoid punishment, and this has become too much for Macarthur.
In her own bed, Vera thinks about Hugo, who said that he couldn't marry her because he didn't have enough money, and that he would have inherited money if Cyril hadn't been born. Vera knew that Cyril wasn't very strong but Cyril kept whining, annoyingly, that he wanted to swim out to the rock. Vera looks at the poem on the wall that says, “Ten little soldier boys went out to dine; One choked on his little self and then there were Nine.” She realizes that this was just like tonight. She can't imagine that Anthony Marston would want to die – or that anyone could want to die. She thinks death is for other people.
Vera is the first to make the connection between the nursery rhyme hung on the walls and the first death. The events of the night have brought back her recurring, yet murky, memory about Cyril and Hugo, although we do not fully understand what happened yet. Her belief that death is for “other people” shows her idea (which other characters share) that she is somehow exempt from the rules and laws that govern human life.