Themes are the fundamental and often universal ideas explored in a literary work.

The Administration of Justice

Most murder mysteries examine justice—its violation, through the act of murder, and its restoration, through the work of a detective who solves the crime and ensures that the murderer pays for his or her deed. And Then There Were None examines justice, but it bends the formula by making the victims of murder people who committed murder themselves. Thus, the killings on Indian Island are arguably acts of justice. Judge Wargrave does the work of detective and murderer by picking out those who are guilty and punishing them.

Whether we accept the justice of the events on Indian Island depends on both whether we accept Wargrave’s belief that all the murder victims deserve their deaths and whether we accept that Wargrave has the moral authority to pronounce and carry out the sentences. At least some of the murders are unjust if we do not consider all of Wargrave’s victims murderers. Emily Brent, for example, did not actually kill her servant, Beatrice Taylor. Thus, one could argue that she deserves a lesser punishment for her sin.

Christie explores the line that divides those who act unjustly from those who seek to restore justice. She suggests that unjust behavior does not necessarily make someone bad and enforcing justice does not necessarily make someone good . Wargrave’s victims, although they have violated the rules of moral behavior in the past, are, for the most part, far more likable and decent human beings than Wargrave. Although Wargrave serves justice in a technical sense, he is a cruel and unsympathetic man, and likely insane.

Read more about justice as a theme in Alexandre Dumas’s The Count of Monte Cristo.

The Effects of Guilt on One’s Conscience

By creating a story in which every character has committed a crime, Christie explores different human responses to the burden of a guilty conscience. Beginning with the first moments after the recorded voice reveals the guests’ crimes, each character takes a different approach to dealing with his or her guilt.

The characters who publicly and self-righteously deny their crimes are tormented by guilt in private. General Macarthur, for instance, brusquely dismisses the claim that he killed his wife’s lover. By the following day, however, guilt so overwhelms him that he resignedly waits to die. Dr. Armstrong is equally dismissive of the charges against him, but he soon starts dreaming about the woman who died on his operating table.

On the other hand, the people who own up to their crimes are less likely to feel pangs of guilt. Lombard willingly admits to leaving tribesmen to die in the African bush, insisting that he did it to save his own life and would willingly do it again. Tony Marston readily owns up to running down the two children, and he displays no sense of having done anything wrong. Neither of the two men gives a moment’s private thought to his crime.

While the ones who do not own up to their crimes feel the guiltiest, no such correlation exists between levels of guilt and likelihood of survival. Conscience has no bearing on who lives the longest, as is illustrated by the contrast between the last two characters left alive, Lombard and Vera. Lombard feels no guilt, and the air of doom that enshrouds the island doesn’t affect him. Vera, on the other hand, is so guilt-ridden that she ends her life by succumbing to the seemingly inevitable conclusion of the “Ten Little Indians” poem and the aura of almost supernatural vengeance that pervades the novel.

Read about the related theme of the psychology of crime in Fyodor Dostoyevsky’s Crime and Punishment.

The Danger of Reliance on Class Distinctions

And Then There Were None takes place in 1930s Britain, a society stratified into strict social classes. These distinctions play a subtle but important role in the novel. As the situation on the island becomes more and more desperate, social hierarchies continue to dictate behavior, and their persistence ultimately makes it harder for some characters to survive. Rogers continues to perform his butler’s duties even after it becomes clear that a murderer is on the loose, and even after the murderer has killed his wife. Because it is expected of a man of his social class, Rogers washes up after people, remains downstairs to clean up after the others have gone to bed, and rises early in the morning to chop firewood. The separation from the group that his work necessitates makes it easy for the murderer to kill him. Additionally, the class-bound mentality of Dr. Armstrong proves disastrous for himself and others, as he refuses to believe that a respectable professional man like Wargrave could be the killer.

Read about the related theme of social class in Charles Dickens’s David Copperfield.