After his wolfdog Hailong sacrifices himself and saves his family from an explosive trap, Erlin takes Hailong's pups to the army so that they can be trained as military dogs to fight the Japanese.

Ma Changqing went deep into the grassroots to understand the situation. He lived in the collective dormitory in the rain and witnessed the practical difficulties of the young workers. At the meeting of the Mining Party Committee, he proposed to solve the housing problem, improve the canteen, prioritize living over production, and propose democratic election of team leaders. Through a series of measures, the mine has undergone great changes. Ma Changqing always does a good job in ideological work in the first place to address the outstanding problems among the young workers.