A recently retired judge, Wargrave is intelligent, cold, and commanding. During his years on the bench, he had a reputation as a “hanging judge”—a judge who persuaded juries to bring back guilty verdicts and sentenced many convicted criminals to death. Christie describes Wargrave as wizened and ugly, with a “frog-like face[,] . . . tortoise-like neck,” and “pale shrewd little eyes”; his ugliness makes his appearance more forbidding. Once the situation on Indian Island becomes clear and the guests realize that a murderer is hunting them, they look to Wargrave for leadership, and he obliges. He is the first to insist publicly that they are dealing with a homicidal maniac, and the first to acknowledge that the killer must be part of their group. When leading group meetings on the island, he often acts like a judge presiding over a court. Wargrave analyzes evidence, authorizes searches both of the island and of people’s possessions, and takes charge of drugs and other potential weapons, ensuring that they are safely locked away.

It is partially Wargrave’s experience with criminal proceedings that makes the others go along with his leadership, but he also has a confidence-inspiring ability to project an air of cold reason in a time of crisis. In a standard detective story, Wargrave’s behavior would make him the detective figure, using his experience with the criminal mind to unmask the killer. But as we learn at the close of the novel, when a local fisherman recovers his confession, Wargrave himself is the killer. He plans the entire enterprise, selects his ten victims, buys the island, and then pretends to be one of the group. Despite his identity as murderer, however, Wargrave is not entirely unlike the detective in a traditional mystery story. Since all of his victims are supposedly guilty of murder, Wargrave, like the detective, acts as an agent of justice, making sure that murderers are punished for their crimes. Nevertheless, in spite of his victims’ obvious guilt and Wargrave’s insistence that he would not let an innocent person suffer, we are unlikely to find him a sympathetic character. Far from being a disinterested agent of justice, Wargrave is a sadist, taking perverse pleasure in murder. As a boy, he killed insects for sport, and he brings the same zeal to his task on Indian Island. He never shows pity for his victims; instead, he regards them as pawns to move around and kill in order to create what he terms a “work of art”—his perfect killing spree.

Vera Claythorne is a former governess who is working as a “games mistress at a third-class school” when the novel begins. She takes a summer job on Indian Island, believing that she has been hired to serve as a secretary to a Mrs. Una Owen. Like the other characters, Vera has a dark secret. At her last job, she was governess to a spoiled little rich boy named Cyril Hamilton. She let Cyril drown so that his relative, Hugo, would inherit his money and then be rich enough to marry her. An inquest cleared her of any wrongdoing, but Hugo, certain that Vera had let Cyril die, would have nothing more to do with her. Throughout the novel, Vera’s guilty memories of her crime plague her. She often thinks of Hugo and feels as if he is watching her.

In some ways, Vera is one of the most intelligent and capable characters in the novel, which explains why she is one of the last people left standing. She outwits the resourceful Philip Lombard, who thinks she is a murderer, by stealing his gun and then summoning up the courage to shoot him when he leaps at her. Despite her strength, however, Vera is not emotionally stable. In addition to her recurrent bouts of guilt over Cyril’s death, she is strongly affected by the almost supernatural nature of the events on the island and prone to attacks of nervous hysteria. More than anyone else, she fixates on the “Ten Little Indians” poem that lends an air of eerie inevitability to the murders. The confluence of these factors—her guilt, her tendency toward hysteria, and her fascination with the nursery rhyme—enables Wargrave to create a suggestive environment complete with a noose and the smell of the sea, which inspires Vera to hang herself and fulfill the last line of the poem.

Philip Lombard has the most mysterious past of anyone on the island. He is a world traveler and a former military man who seems to have served as a soldier of fortune in Africa. In the epilogue, one of the policemen describes him as having “been mixed up in some very curious shows abroad . . . [the] sort of fellow who might do several murders in some quiet out-of-the-way spot.” He comes to Indian Island after Isaac Morris hires him, supposedly because Mr. Owen needs a “good man in a tight spot.” Clearly a dangerous man, Lombard carries a gun and is frequently described as moving “like a panther.” He is bold enough to initiate several searches of the island, perceptive enough to suspect Judge Wargrave of being the killer, and brave enough to voice his suspicions. Lombard is also honest: he owns up to his past misdeeds. When the recorded voice accuses him of leaving twenty-one men from an East African tribe to die in the bush, Lombard cheerfully admits to it, saying there was only enough food for himself and a friend, and so they took off with it. The other characters cannot bring themselves to admit their own guilt, but Lombard has no such qualms.

Lombard does display a weakness, however, that ultimately brings about his downfall: his chivalrous and old-fashioned attitude toward women. In the first group conversation about the murders, he suggests excluding the women from the list of potential suspects, since he considers them incapable of homicidal behavior. Lombard’s tendency to underestimate women enables Vera to steal his gun and shoot him when he jumps at her. In a strange way, his death unites Vera and Lombard—they are the only characters to die at the hand of someone other than Wargrave.