Return to the Ruins Recorded in Xuyuan

Five pieces of jade, five strangers. They didn't know each other, but they were forced to get together because of a bronze letter, and they gradually became dependent on each other in their lives. Antique restorer Lin Qingshu, gentle medical student Fu Lu, arrogant acoustics researcher Yunyao, city government engineer Mu Jinzhi, and a silent seven-year-old boy Lin Man. Jade is the key, the forest is the keyhole, and "Xu" - the unknown space deep underground - is the door.