During the most difficult years of the Anti-Japanese War in 1941, the Japanese invaders and the Kuomintang's forces colluded with each other harassing the Shaanxi-Gansu-Ningxia border area. Because of this, people faced many difficulties. A charcoal burning team of Eighth Route Army in Yan'an responded to the call of the Party Central Committee and Chairman Mao to "do it yourself, get enough food and clothing". Under the leadership of the captain Zhao Changlong, they rush to the deep mountains and old forests to cut through thorns, camp, and dig kilns to burn charcoal.