A group of young workers is building a strategic highway for the Chinese army. Jin started to work as a builder at the age of ten with his father. Always smiling, he can overcome any obstacle. Zhang does not speak much and looks sad— he’s a sensitive man. Zheng Jun, a student, is a refugee from Manchuria which has just been occupied by the Japanese. There are also Han, the little thief and Luo, the eternal dreamer. Each has hi sown temperament but they all get on well
and always stick together. They meet two grils, Dingxiang and Moli, who work at the canteen. Dingxiang is in love with Luo. Moli thinks they’re all nice boys and loves them all. Jin and his friends are respected by their fellow workers for their courage and because they always stand together up to the foreman. Japanese spies have got in touch with Hou Tian, a local leader, as they want to stop the building of the road at any cost. Hou Tian invites Jin and his friends to his house and offers them money so that they stop working. Jin refuses, they are ail imprisoned and tortured.