"The Beiyang Case" mainly tells the story of several unsolved cases left over from the turbulent period of the Republic of China. The century-old secret triggered by a "hundred corpses crossing the river" is about to be revealed, and the process of solving the case is beyond the usual routine. This film is composed of different stories, with unit-solving as the main theme, and is linked together. It is fantasy, adventure, and suspenseful, creating a mysterious and tense story atmosphere. The plot is brain-burning and attracts people to explore it.