A remote schoolhouse perched on the edge of a French Algerian plateau is almost buried by an unusually heavy and early blizzard. Daru, a French schoolteacher who lives there alone, finds his isolated routine disrupted by the arrival of Balducci, a weary police officer, and another man on foot who’s clearly his prisoner. Balducci is escorting this man to trial, as he has murdered his cousin in a heated argument. The gendarme—a term in French meaning “police officer”—abruptly dumps the responsibility of the prisoner on Daru. He explains that Daru must deliver the Arab to the authorities in Tinguit. Daru is caught off guard and tries to decline the request, as he feels it’s dishonorable. Balducci insists, however. Although Daru continues to protest, Balducci only consents to leave after compelling Daru to sign a form stating he has custody of the Arab. Balducci’s feelings are hurt by Daru’s harsh words, but he still promises not to incriminate Daru when he returns to the police headquarters.
Daru offers the nameless prisoner some food and a place to sleep for the night. He tries to question the prisoner about why he committed the crime, but the Arab refuses to answer straightforwardly. Unsure how much French the Arab understands, Daru gives up and tries to sleep. During the restless night, he repeatedly thinks he hears the prisoner trying to escape, and secretly hopes he will. However, each time he could break free, the prisoner returns calmly and silently to his captivity. Daru knows he has been placed in an impossible position, as he is caught between his legal duty as a French citizen and his growing sympathy for the silent Arab. As he sees the Arab eating, drinking, and sleeping, he thinks about how living in close quarters can make allies out of any two people.
The next morning, Daru makes a decision. He and the Arab leave the schoolhouse, although Daru is suspicious that someone else is there hiding and observing them. He leads the prisoner to a remote spot on the plateau. He then explains to the Arab that there are two paths he can choose from. One leads to Tinguit, a murder trial, and probably death. The other disappears into the vast desert, but holds the potential for safe haven with a nomadic tribe. He offers the Arab money and provisions, leaving the choice of paths entirely in his hands, and walks away.
The Arab hesitates, the weight of the decision paralyzing him, but Daru has already turned his back. When Daru looks around, however, he sees the Arab trudging down the path that leads to the police headquarters. Daru returns to his schoolhouse, trying to understand why his former prisoner chose to turn himself in.
As Daru muses on this puzzling choice, he discovers a chilling message scrawled on his blackboard: “You handed over our brother. You will pay for this.” This is presumably written by Algerian resistance forces who believe the schoolteacher has turned the Arab in. Even though he didn’t, the consequences are the same as if he had taken the Arab to Tinguit himself. Standing at the window, Daru gazes out at the enormous expanse of craggy land to the east, waiting to learn how he will “pay.”