Eight strangers are invited by a mysterious person named U. N. Owen to a luxurious mansion on an island off the coast of Devon. Waiting for them on the island are the housekeeping couple, Mr. and Mrs. Rogers. After dinner, the group hears a recording in which a disembodied voice exposes each of them as a murderer whose crime has has gone undetected and unpunished. Playboy Tony Marston is accused of driving recklessly and causing the deaths of two young people; Mr. and Mrs. Rogers are accused of murdering their aged employer by withholding medication from her; General Macarthur is accused of arranging for the death of a fellow officer; Emily Brent is blamed for the death of her maidservant; Justice Wargrave is blamed for sentencing a possibly innocent man to death; Dr. Armstrong is accused of killing a patient; former policeman William Blore is accused of knowingly sending an innocent man to prison, where he died; soldier of fortune Philip Lombard is accused of allowing native Africans to die of starvation; and former governess Vera Claythorne is blamed for the drowning death of a boy in her care.
The guests defend themselves, determined to preserve their status as acceptable members of English society. Lombard justifies the deaths of the natives in modern, social Darwinist terms, citing the law of self-preservation and the superiority of the Anglo-Saxon race, while Blore asserts that he was simply doing his job. Armstrong admits his guilt, but uses his inebriated condition as an excuse. Marston insisted the deaths of the two young people were accidental.
Marston soon dies from drinking cyanide-laced whiskey. Justice Wargrave immediately takes command, suggesting one of the group is in fact “Mr. Owen,” who is toying with them sadistically. Comparing notes, they realize that none of them knows their host and that his name, U. N. Owen, translates into “unknown.” Shaken, the guests further reflect on the accusations against them. Rogers admits that he and his wife inherited money from the woman from whom they withheld medicine; his wife’s nervous demeanor further confirms their guilt. General Macarthur breaks down, admitting that the young man he sent to his certain death was his wife’s lover.
Ten figurines are arranged on the mansion’s dining room table, representations of the characters in a nursery rhyme that is also framed and hung in each guest’s...
(The entire section is 981 words.)