Grand often talks about Jeanne to Rieux; he, in turn, unburdens his worries about his own wife. Rieux verifies his suspicion that her health is failing with the sanitarium authorities. Rieux hardens his heart against the desperation of the families of plague victims in order to continue doing his work. Meanwhile, Tarrou devotes a great deal of attention to Cottard in his notebooks. Cottard has always lived with a constant sense of fear. He is happier now that he no longer bears that burden alone. He craves human contact, but he distrusts everyone as a possible police informant. During the plague, everyone craves this same contact, but they must also distrust everyone as a possible carrier of the deadly plague. Tarrou writes of a performance of Gluck's Orpheus. The actor playing Orpheus collapses on the stage in the manner of a plague victim just as Eurydice is taken back to the Underworld. Calm at first, the audience eventually stampedes for the exit.
When a definite time for his escape is finally set, Rambert chooses to stay because he is too ashamed to leave during such a crisis. Meanwhile, Castel finishes the first batch of serum, and Othon's small son is the first to receive it. The child suffers terribly before dying as Paneloux, Rieux, and Tarrou watch in horror. Rieux lashes out at Paneloux, shouting that the boy was an innocent victim. Paneloux understands that Rieux's anger is directed at his sermon some months earlier.
In the deadly grip of the plague, the public has turned its attention from religion to superstition. When Paneloux delivers his next sermon, the church is emptier than before. He maintains that his first sermon is still relevant. He declares that the unanswerable question of an innocent child's suffering is God's way of placing the Christian's back to a wall. It tests his faith because it requires him to either deny everything or believe everything. Paneloux cites a chronicle of a previous epidemic in which only four monks survived, three of whom fled the stricken city. He declares to his congregation that each of them should choose to be the one who stays behind. He argues against mute resignation because there is no excuse to give up the struggle. Soon thereafter, Paneloux falls ill, but he refuses to consult a doctor. His symptoms do not conform to those of the plague, so when he dies, Rieux marks him as a "doubtful case."
When his period of quarantine ends, Othon volunteers to remain in the camp to help out with the anti-plague effort because it would make him feel "less separated" from his son. Rieux is amazed to see gentleness in Othon's character because he has always regarded him as a steely, inflexible man. During Christmas, Grand is overcome with depression because it reminds him of his courtship with Jeanne. He falls ill with the plague and Rieux burns his papers at his request. Most of the papers concern the opening line to Grand's book, but one sheet contains an unfinished opening to a letter addressed to Jeanne. Grand makes a surprising recovery, and better yet, the plague deaths overall begin to decline. Rieux's asthma patient gleefully declares that the rats are back.
Earlier in the novel, Rambert accused Rieux of using the language of abstraction instead of the language of the heart. He came very close to accusing Rieux of indifference. It is true that Rieux dispensed with sentimental pity. It is also true that he hardens his heart against the suffering of the plague victims, but it is not true that he is indifferent to their suffering. Indifference is a state of inaction or denial in response to other people's suffering. Rieux must harden his heart against his own suffering in order to continue contributing to the anti-plague effort. His wife is slowly dying in a sanitarium 100 miles from Oran while he is trapped in the city.
The desire for human contact is a powerful human need, especially in times of suffering. Now that everyone suffers from a constant sense of fear, Cottard feels less alone. However, he does not really break free from his alienation. Constant fear breeds distrust. Everyone in Oran must distrust everyone else as a possible carrier of the plague. They flock to movies and cafes to feel less alone, but it is unwise to assume that mutual escapism really constitutes a breach of their collective isolation.