Era background: The turbulent 1930s and 1940s of the Republic of China, from the isolation period of Shanghai to Chongqing, the capital of the Anti-Japanese War, until the dawn of Yan'an.
Core character: Lu Zhen, 26 years old, is a female forensic doctor and detective in the French Concession in Shanghai. She inherits the legacy of her murdered father and walks at the intersection of light and darkness with a scientific spirit and tenacity.
The main story line: A seemingly ordinary case of gas poisoning of a famous Peking Opera actress plunged Lu Zhen into an unfathomable mist. The blood-stained ivory fan at the crime scene leads to a missing Ming Dynasty secret treasure "Mountains and Seas and Strange Beasts", which also involves the unfinished ideals left by the Taiping Heavenly Kingdom. Twelve ivory fans with hidden codes and twelve volumes of maps of mountains and seas with exotic animals pieced together a secret map related to national treasures, history and national memory.
