When the grandfather, a farm owner, anticipated based on various signs that the coming winter would be long and harsh, and bought extra supplies and expanded the basement, his sons laughed at him.
Now that the long, harsh winter has arrived unexpectedly early, the sons are grateful to their grandfather.
The adults (grandfather, eldest son, second son and his wife, the second son's wife's younger brother, and third son and his wife) take turns patrolling the inside and outside of the farm in pairs, and also take turns keeping watch through the night.
The two young grandchildren (the second son's daughter and son) are having a fun time every day because they are used to staying in the farm during the winter anyway, and the adults are spoiling them more than usual.
They are a bit unhappy that the TV and radio are broken, the telephone lines are cut by an avalanche, the only road to town is blocked by an avalanche, and the oldest aunt (the eldest son's wife), who was visiting a friend in town, cannot come back. However, they are eagerly looking forward to spring, when they can all have a picnic, go to school, and reunite with their friends.
Wary of starving feral dogs, the adults set traps everywhere and patrol while carrying guns.
Gunshots ring out almost every day, and the adults return with grim expressions.
The adults, who show gentle and reliable faces in front of the two grandchildren, discuss the future with serious expressions at night.
The eldest son gets drunk and rages, saying, "I'll never see my wife again!" while his younger brothers soothe him by saying, "Let's go look for her when the snow melts."
(At this point, the reader might wonder: Is visiting a friend in town really the truth? Is it a lie told to protect the children's ears, and is it actually an affair and elopement?)
In reality, this "early-arriving, long, and harsh winter" is a nuclear winter. The avalanches and cut telephone lines were caused by nuclear war, and "the TV and radio are broken" is a lie deliberately told so as not to shock the young grandchildren about the destruction of broadcasting stations.
The "feral dogs" are actually the townspeople who somehow survived, suffering from radiation sickness and starvation.
The family kills them to protect their own, but deliberately calls them "starving feral dogs" to protect their own sanity.
The two daughters-in-law have gloomy faces, whispering that they must hide the bodies before letting the children outside when spring comes, as the children shouldn't see them…
The third son has been losing a lot of hair lately.
He forces a laugh, joking, "I don't want to go bald before the old man, HAHAHA."
The story ends with a page depicting the contrast between the innocent grandchildren and the gloomy-faced adults, with a mushroom cloud and radioactive fallout mixing with the snow in the background.