The main content is that in Jing'an, Shanghai in the 1930s, urban planner Lin Yu accidentally discovered a dusty transistor and half an encrypted diary in the old wall mezzanine of No. 9 Fukangli. Through modern AI algorithm deciphering, a dusty past story about the origin of "red radio waves" has been revealed. The novel adopts a two-line narrative. One line is the search and puzzle solving from a modern perspective. The other line is the life-and-death game between Pu Qiuchao and Zhang Chenchuan, the underground party members in the 1930s, who used the cover of "fake couple" to send reports and pass information between small rooms under the white terror.
