When Darkness at Noon begins, the protagonist, Nicholas Salmanovitch Rubashov, finds himself having been recently enclosed inside a prison cell, where it seems he knows what will happen to him next. The narration flashes back to a few hours earlier, when Rubashov was awakened from a dream—a recurring dream that he was being arrested—to find himself being arrested in real life by two officials. They arrive to the door of the porter Wassilij, who, having fought with Rubashov in the war, is fiercely loyal to him. Rubashov is to be arrested on the orders of No. 1, the leader of the unnamed (but recognizably Soviet Communist) Party. Rubashov accompanies the officials to the prison but, as a former Party bureaucrat himself, he is rather dismissive towards this younger generation, which seems to lack the subtlety and intellectual prowess of his own. When he arrives in prison, Rubashov claims to have a toothache (a pain that will recur every time he thinks about individuality), so he’s left alone. He “talks to” one of the prisoners in a neighboring cell, whom he refers to only as No. 402, through a kind of Morse Code language conveyed by tapping against the wall. 402 is a counter-revolutionary who still supports the monarchy that was in power when the revolutionaries took over, but he’s mostly interested in spreading prison gossip and talking about women.
Rubashov thinks back to a memory from years before, when he’d been a diplomat in Germany spreading the Party message abroad, and he’d had to meet with a regional leader of the Party named Richard. They’d met at a picture gallery, and while keeping himself focused on a Pietà painting of the Virgin Mary, Rubashov had told Richard that it was a mistake for Richard to have printed his own pamphlets for the cause rather than using the official Party message. Richard had felt like he could modify the Party message to best recruit new people, but Rubashov told him that the Party, since it represented the revolutionary idea in history, could never be mistaken and therefore its message shouldn’t be modified. Richard grew increasingly desperate as he realized that Rubashov might be reporting him to the Central Committee, but Rubashov remained cold and featureless in response.
Back in the prison cell, Rubashov, who’s feeling increasingly anxious without cigarettes, learns through No. 402 that there’s a new political prisoner, who seems to keep looking up at Rubashov’s cell from the prison courtyard: Rubashov doesn’t recognize him and just thinks of him as Hare-lip. Rubashov muses about how he’s gotten to this point and about why he’s been arrested: it seems like somewhere, somehow, the Party has gone awry, though Rubashov struggles to understand how, given that the Party represents history itself. Rubashov thinks back to another case, when he had to go to Belgium and explain to a group of people—including Little Loewy, a fervent supporter of the Party who had risked his life multiple times for the cause—that the Party was going to renege on its pledge to boycott fascist countries. Little Loewy refused to accept this because he considered it to be a betrayal of the ideals of the revolution. When Little Loewy realized that the Party would accept no deviation from its official policy, he hanged himself. Rubashov starts thinking about specific details from his time with Little Loewy and Richard, and he is troubled by them.
Eventually Rubashov is taken to be interrogated by his old friend and fellow soldier, Ivanov. Ivanov seems to recognize that Rubashov isn’t guilty of treason and plotting to kill No. 1, but Ivanov says that it’s best for them to accept what’s necessary for the Party, and for Rubashov to sign a statement saying he was a member of the opposition. This way the Party will get its public confession, and Rubashov won’t have to be executed. Rubashov, though, suddenly wants to rebel against such pristine logic. He continues to think through his own understanding of the laws of history, and about whether his choices (or No. 1’s choices) will be absolved over time or will have to be paid for. At the next interrogation, Ivanov is accompanied by Gletkin, who’s a member of the new generation and is far more humorless than Ivanov. Gletkin seems to genuinely believe that whatever the Party says is “truth,” rather than simply understanding the Party logic as expedient. Gletkin thinks Rubashov will buckle under torture, though Ivanov is confident Rubashov just needs time to think through the logic of his predicament.
Rubashov has another flashback to an affair he had with Arlova, his secretary. Arlova was eventually appointed librarian at the office where he worked, but she was then accused of not replacing the books on the shelves with more adequate, “truer” versions of Party history. Rubashov stalled but ultimately did betray her, and she was executed. He thinks back now to the details of her body, and he grows increasingly troubled by them. Meanwhile, a new prisoner arrives, No. 406 or Rip Van Winkle, who had spent 20 years in solitary confinement in another country and is now in an entirely new world with entirely different ideological standards and claims to truth. That afternoon, Rubashov is taken to the barber, who shoves a note into his collar telling him to “die in silence.” Rubashov thinks it might be possible that he will actually capitulate to Ivanov’s offer. Rubashov is taken outside to exercise that afternoon—Ivanov has been improving Rubashov’s standard of living while he deliberates—and he talks a little to Rip Van Winkle.
Almost two weeks after Ivanov’s offer, the mood seems different in the prison, and 402 tells Rubashov that a political prisoner is being executed. The prisoner is Michael Bogrov, Rubashov’s old friend and mentor. As he’s led down the hall, Bogrov cries out Rubashov’s name. Rubashov is stricken: suddenly the cold logic that has ruled his dealings with the Party his whole life is thrown into question. Rubashov returns to be interrogated by Ivanov and tries to explain this to him, but Ivanov dismisses him, saying that his moral scruples are relics from bourgeois, nineteenth-century ethics, which have no place in this revolutionary society. Rubashov does think that this society is exceptional, but now he argues that the exceptionalism lies in the death and destruction enacted by the Party. After a long intellectual conversation, Ivanov visits Gletkin and says that his own method works better than Gletkin’s—Gletkin’s the idiot who should be shot.
Rubashov continues to think through an intellectual theory of history that would account for his situation. After meeting another prisoner, a reactionary peasant, in the prison courtyard, Rubashov decides to capitulate. No. 402 thinks Rubashov is disgracing himself, but Rubashov seems unfazed. After waiting to be taken to Ivanov, Rubashov is eventually led into another office: this time it’s Gletkin who’s interrogating him, as Ivanov has been arrested for treason. Gletkin isn’t interested in the kind of intellectual banter and argumentation that Ivanov was: he seriously, gravely lists the charges against Rubashov, who’s incredulous that Gletkin actually seems to believe the charges rather than just act as though they are true. Gletkin brings in Hare-lip, who, it turns out, is the son of Rubashov’s old friend Professor Kieffer. Kieffer was executed for refusing to rewrite the history books to align with the new Party narrative of history. Hare-lip describes a conversation between Rubashov and Kieffer in which Rubashov belittled No. 1’s techniques and argued for pragmatism rather than earnest belief in the Party decisions. Hare-lip ends by claiming that Rubashov then wanted to hire Hare-lip to murder No. 1 with poison. Using the skills of logical reasoning, Rubashov proves that this charge is impossible, but he feels suddenly apathetic when he knows it won’t make a difference. Gletkin, throughout the interrogations, keeps a harsh light on Rubashov and deprives him of sleep so that it seems like the world of dreams and that of reality melt into one. Rubashov could deny everything or admit to everything, but he feels a strange sense of individual honor that forces him to go through each charge one by one and take a brief sense of triumph in his small successes. Eventually Gletkin does go off the script a little, telling Rubashov about his childhood as a peasant and how he’s convinced that the masses need straightforward doctrines and well-performed confessions in order to further the Party cause.
Finally, Rubashov does sign a document agreeing to the charges, and Gletkin tells his stenographer that his approach was right: physical deprivation is always the way to get people to buckle. The narration shifts to the porter Wassilij and his daughter, Vera, who is reading him the transcript of Rubashov’s trial and remarking about how Rubashov must be guilty. Wassilij, though, thinks of Rubashov as a kind of Christ figure, sacrificed for others. Wassilij has to be careful to hide some of his Christian rituals (like praying) from his daughter, who he knows would love nothing more than to have him pushed out of the apartment they share so that she can move in with her fiancé. When the narration returns to Rubashov’s point of view, he’s still obsessed with thinking through his theories of history. He’s certain now that there’s no way of resolving the ideological contradictions in the Party between the individual and the collective, but he imagines that there might be a way of doing so in the future, in another society. Before he dies, he thinks of his dream of being arrested, and he wonders for one final time what his death might mean, if anything. A silence reigns after his death.