The novel expresses the author's disillusionment with Bolshevism, Stalinism, and the ideology of the Communist Party of the Soviet Union at the outset of World War II.

In 1998, the Modern Library ranked Darkness at Noon number eight on its list of the 100 best English-language novels of the 20th century, even though Koestler originally wrote it in German.

Rupert Hart-Davis, Koestler's editor at Jonathan Cape in London had misgivings about the English text but agreed to publish it when a request to Oprecht for his copy went unanswered.

[1] The new title is a reference to Job 5:14: "They meet with darkness in the daytime, and grope in the noonday as in the night"— a description of the moral dilemmas faced by the book's protagonist, as well as Koestler's own escape from the Nazis.

According to Scammell, "[Hardy] had been forced by circumstances to work in haste, with no dictionaries or other resources available for consultation, which exposed her understandable lack of familiarity with the Soviet and Nazi machinery of totalitarianism.

[6][7] In his autobiographical The Invisible Writing (1954), Koestler stated that he finished Darkness at Noon in April 1940, after many troublesome months of 1939, caused mainly by financial difficulties and the later outbreak of World War II.

"During the next three months I finished the novel in the hours snatched between interrogations and searches of my flat, in the constant fear that I would be arrested again and the manuscript of Darkness at Noon confiscated".

[8][9][7] Waiting in Lisbon for passage to Great Britain, Koestler heard a false report that the ship taking Hardy to England had been torpedoed and all persons lost (along with his only manuscript); he attempted suicide.

Darkness at Noon is an allegory set in the USSR (not named) during the 1938 purges as Stalin consolidated his dictatorship by eliminating potential rivals within the Communist Party: the military and the professionals.

[citation needed] Koestler drew on the experience of being imprisoned by Francisco Franco's officials during the Spanish Civil War, which he described in his memoir, Dialogue with Death.

This is the faith that makes the abuses of the regime tolerable as the men consider the suffering of a few thousand, or a few million people against the happiness of future generations.

Despite 20 years of power, in which the government caused the deliberate deaths and executions of millions, the Party does not seem to be any closer to achieving the goal of a socialist utopia.

Several days later, Party publications denounce the entire cell by name, virtually guaranteeing arrest by the Belgian authorities, who were trying to suppress communism.

Their conversation continues the theme of the new generation taking power over the old: Ivanov is portrayed as intellectual, ironical, and at bottom humane, while Gletkin is unsophisticated, straightforward, and unconcerned with others' suffering.

Rubashov signs a letter to the state authorities in which he pledges "utterly to renounce [my] oppositional attitude and to denounce publicly [my] errors".

Rubashov notices that news of Ivanov's fate has not made a meaningful impression on him, as he has evidently reached a state that precludes any deep emotion.

As he confesses to the false charges, Rubashov thinks of the many times he betrayed agents in the past: Richard, the young German; Little Loewy in Belgium; and Orlova, his secretary-mistress.

[32] The New York Times described Darkness at Noon as "a splendid novel, an effective explanation of the riddle of the Moscow treason trials...written with such dramatic power, with such warmth of feeling and with such persuasive simplicity that it is absorbing as melodrama".

[citation needed] Orwell wrote, "Rubashov might be called Trotsky, Bukharin, Rakovsky or some other relatively civilised figure among the Old Bolsheviks".

[35] Orwell's Homage to Catalonia, which was bout the Spanish Civil War, sold poorly; he decided after reviewing Darkness at Noon that fiction was the best way to describe totalitarianism, and wrote Animal Farm and Nineteen Eighty-Four.

[31] When reviewing Nineteen Eighty-Four, Arthur Mizener said that Orwell drew on his feelings about Koestler's handling of Rubashov's confession when he wrote his extended section of the conversion of Winston Smith.

[37][38] According to his collaborator Belu Zilber, Pătrăşcanu read Darkness at Noon in Paris while envoy to the 1946 Peace Conference, and took the book back to Romania.

According to Kenneth Lloyd Billingsley in an article published in 2000, communists considered Koestler's novel important enough to prevent its being adapted for movies; the writer Dalton Trumbo "bragged" about his success in that to the newspaper The Worker.

[39] U.S. Navy admiral James Stockdale used the novel's title as a code to his wife and the U.S. government to fool his North Vietnamese captors' censors when he wrote as a POW during the Vietnam War.

[42][43] The IRD bought thousands of copies to inflate sales statistics, and also used British embassies to translate and distribute the novel to be used as Cold War propaganda.

Until this period of adaptation runs its course, Rubashov comes to accept that a totalitarian government is perhaps not unjustified as people would only steer society to their own detriment anyway.

Every jump of technical progress leaves the relative intellectual development of the masses a step behind, and thus causes a fall in the political-maturity thermometer.

It takes sometimes tens of years, sometimes generations, for a people's level of understanding gradually to adapt itself to the changed state of affairs, until it has recovered the same capacity for self-government as it had already possessed at a lower stage of civilization.

(Hardy translation) And so every leap of technical progress brings with it a relative intellectual regression of the masses, a decline in their political maturity.

At times it may take decades or even generations before the collective consciousness gradually catches up to the changed order and regains the capacity to govern itself that it had formerly possessed at a lower stage of civilization.