In the city of fog, memory restorer Lin Mo can sneak into other people's broken memories. He originally thought that Mrs. Chen Shuyun's commission was just to find a lost music box. However, when he went deep into the island of memory, he discovered that there was a dangerous secret buried under the dusty past. Every restoration is an adventure closer to the truth, and what echoes is not only the melody, but also the forgotten sins and lies.
