The film is set in an unspecified
Western Bloc city after a
nuclear war; the city is a
radioactive ruin. The main character, Professor Larsen (
Rolan Bykov), is a recipient of the
Nobel Prize in Physics who lives in the basement of a decimated museum along with his sick wife Anna and several other museum employees. He compulsively composes mental and written letters to his son Eric, though he has no way of contacting him or even verifying that he is alive. Larsen believes the war has ended and that more surviving humans exist outside the central bunker, but nobody else believes his theories. Larsen visits an
orphanage, where the surviving children's current caretaker explains that she's thinking of evacuating to the central bunker; to Larsen's disapproval, she says that it is likely that the children will not be permitted to go with her because they have been traumatized into a state of
catatonic withdrawal. Larsen learns that he too might be prohibited from entering the central bunker due to his old age. With Anna suffering from the effects of
radiation sickness, Larsen sneaks past several military patrols during curfew hours in an attempt to find medicine. At the medical station, the doctor has no painkillers but gives Larsen a can of food in the hope that he can trade it for medication on the black market. The doctor then informs Larsen that the medical staff have been ordered to evacuate to the central bunker, where they and the other survivors will remain in perpetuity. Narrowly escaping a military raid as he barters with a privateer, Larsen returns to the museum with the painkillers only to find that Anna has died. The other museum employees bury her body. In one of his letters to Eric, Larsen speculates, with the conviction of certainty, how the war started: a computer error triggers the first strike command. A military technician recognizes the error and has a chance to cancel the launch, but he's carrying a cup of coffee, which slows him down as he makes his way to the errant computer. He arrives too late by seven seconds; the war begins, and the operator hangs himself. The letter ends with Larsen wondering if "there is something in this number," seven, "even if we forget the commonplace things." In a flashback, Larsen makes his way to the central bunker in an effort to find Eric shortly after the outbreak of the war. After sneaking into a medical facility, he enters the children's ward, where he is aghast to find all the children sick, traumatized, horribly injured, and screaming in agony. In the present, Larsen is in the museum basement with the other survivors. A museum employee ruminates that human history has ended and that mankind itself was doomed from the start. The employee then lies down in a nearby grave and shoots himself dead as the others watch passively and his adult son slips into madness. Later, while salvaging books from a flooded library, Larsen talks with a man who responds to his hopefulness by saying that their situation is the fulfillment of
biblical prophecy. Larsen visits the orphanage, where he learns that the children will not be permitted to enter the central bunker. The caretaker and the remaining museum employees evacuate while Larsen decides to remain behind to look after the children alone. On
Christmas Day, Larsen creates a makeshift
Christmas tree out of sticks and candles while the children, who have begun to trust him, design
Christmas ornaments with which to decorate it. In his final letter to Eric, Larsen writes that he has finally found purpose in life, and he implores his son not to leave him alone in the world. The final scene is narrated by one of the children, who explains that Larsen died some time later. Convinced even on his deathbed that human life exists elsewhere, he told the children to leave the museum and seek other survivors while they still have the strength. The film ends with the children--now revealed to be eight in number--wandering through the apocalyptic landscape together, their fates unknown. ==Cast==