It tells the story of Li Mo, a modern railway worker, who travels back to the Zhenguan period during the night shift. With the modern technology and engineering thinking in his toolkit, he started with a piece of "rail from the sky", promoted the concept of standardization in the Tang Dynasty, overcome the technological gap, started with wooden-clad iron tracks, and gradually built a railway system that spans time and space, trying to reshape the Tang Dynasty's transportation and imperial structure with the blood of steel rails.
