In a certain house during the Xining period, young Ni Quan was looking at a volume of "Mengxi Bi Tan" with excitement. He was not studying the scriptures, but he took the skillful hand A Yuan and his official friend Bizhong to restore the phenomenon of "the compass tilts eastward" recorded by Shen Kuo. When the magnetic needle made by the thread suspension method really pointed steadily and slightly in the wrong direction, the doors and windows of the study room automatically moved without wind, emitting a strange resonance. The three of them looked at each other and realized that the seemingly plain records written by Shen Cunzhong might be a key to the unknown. From the exquisite calculations in the "Rhythm" volume to the star map deduction in the "Xiangshu" volume, from the movable type printing in the "Techniques" volume to the mystery of meteorite iron in the "Weird Things" volume, they will follow the ancient texts and embark on a journey of exploration that transcends the times with a rigorous attitude. What awaits them is the secret message hidden deep in the rotation of the Big Dipper, or is it the mysterious pearl bigger than a walnut in the "Secret Land of Zeguo"?
