In this future city wrapped in steel and neon, there are some traces of sin that, even if washed away by time, will leave a faint "echo" in the space. Ling Su, a special being who can "hear" these remaining emotions and memory fragments, is like a ghost wandering between reality and the past, forced to feel the most extreme pain and ecstasy of others. When he was involved in a bizarre secret room murder case, he met Shen Yi, a calm, rigorous detective who only believed in evidence. One relies on super-sense and the other relies on logic. Two completely different people are forced to team up. Starting from a seemingly simple case, it is like pulling the thread of a sweater, gradually unraveling a huge conspiracy about memory transplantation, personality tampering and the boundaries of human nature. And Ling Su was horrified to discover that the truth he was searching for ultimately pointed to his dusty and untouchable past. The echoes he heard might not just be other people's stories.
