Yuan Shan is a railway track inspector deep in the Qinling Mountains. In Yuan Shan's working team, more than ten track inspectors are responsible for different sections, and they seldom meet each other. The only thing that can bring them news from the outside world is the locomotive passing by here. Beside a tunnel, there is a red clay house where Yuan Shan lives alone, which is also Yuan Shan's home. Yuan Shan measures the rails stretching to the distance with his footsteps, greets the sunrise, and sees off the sunset, living a peaceful and simple life.