During the Anti-Japanese War, a team of the Eighth Route Army came to Ma Muchi, a fortress village in the Yimeng Mountains, and they were accompanied by cows donated by international friends. The villagers who had lived in the mountains for many years had never seen such black and white cows with plenty of milk, and they were amazed. Soon, the Japanese ship-jiri troops approached, and the Eighth Route Army retreated urgently, entrusting the cows to the villagers to feed before leaving. The poor and timid villagers were worried that the cows would bring disaster, so they selected the cattle breeder by grabbing red beans. The young widow Jiuer (played by Yan Ni) helped the poor Niu Er (played by Huang Bo) to draw lots, and finally made Niu Er the unlucky "lucky man". After the brutal and bloody sweep, all the villagers were killed, and only Niu Er and the cows became survivors. Before they could get a respite, another team of Japanese troops passed by and left the wounded here. From that day on, Niu Er, who was responsible for protecting the cows, tried his best to deal with the Japanese army, bandits, quack doctors and other people, and his stubborn partner also gave him a headache...