It is a harsh winter in the 1970s with scarce supplies. Jiang Liang, the third son of the Jiang family, goes missing after saving someone. His wife Wang Yunfang breaks her leg. She and her two children, Jiang Xiaoxiao and Jiang Han, are driven out by the cruel grandmother and left in a run-down cottage. In despair, the siblings find their cellar leads to the modern world. They collect scraps and sell mountain goods there for food and medicine to support their mother. Meanwhile, their greedy uncle’s family keeps bullying them. They get help from neighbor Lu Chen, the village chief, and wealthy Lin Wanting. At last, the kids rescue their father Jiang Liang from an illegal brick kiln. The whole family works together, trading goods through the cellar to escape poverty.
