On September 18, 1931, the Japanese invaders occupied Northeast China and attempted to use the rich war resources in Northeast China to realize their ambition to swallow up China and rule the world. The Chinese nation also entered a dark period. But the Chinese nation is a nation that is not afraid of power and is not afraid of sacrifice for freedom. Under the leadership of the Communist Party of China, all ethnic groups, classes, and parties across the country united to form a national anti-Japanese united front and began the arduous and arduous Anti-Japanese War with great sacrifices. "Hard Bones" relies on this real historical background to tell an unknown story of the War of Resistance. Every time the Chinese nation is in danger, there are always some hard bones who stand up. On the black land with cold winds and heavy snow, a special armed force of the Anti-Japanese United Army, the Anti-Japanese United Snow Wolf Sharp Knife Team, is active. This group of hard bones has been in the white mountains and black waters, the forests and snowy plains, and has been fighting together for fourteen years. They have never surrendered and never stopped fighting. They frightened the Japanese. They are about to usher in the dawn of victory. This group of hard bones in "Hard Bones" has only one belief in their hearts: the Chinese nation cannot be humiliated and the Chinese people cannot be bullied. As the end of the world approaches, the Japanese Kwantung Army is unwilling to accept defeat and attempts to make a last-ditch effort. Their lifeline is the 17 military fortresses secretly built on the Sino-Soviet border, known as the "Oriental Maginot Line". These fortresses are the biggest obstacle to the Soviet Red Army's counterattack. If they are not investigated clearly, huge sacrifices will occur. In order to reduce sacrifices, it is necessary to obtain the Japanese fortress force deployment map. This is a difficult and ultimate task. Our hero, Yang Ziliang, the captain of the Snow Wolf Sharp Knife Team, took the initiative to volunteer to gnaw on this hard bone. A desperate battle between the iron-blooded warriors and the enemy with their lives begins...