When Hu Bayi's distant nephew Lao Jiu broke into the cliff of Yuanjiang River in western Hunan to save his grandmother from a strange illness, he did not expect that half of the map left by Hu Bayi actually pointed to a "living burial mausoleum" that had been banned by the Tujia people for generations - nine hanging coffins hanging upside down from the cliff, arranged with the Big Dipper, and the blood-colored totem "No strangers allowed to enter" was engraved on the bottom of the coffins.
In order to find the legendary "Scale-Removing Grass", Lao Jiu was forced to team up with Shao Ye, a descendant of the Banshan Sect. One knows the secrets of Feng Shui, and the other is good at breaking formations, but neither of them can figure out the "flying stone trap" and "corpse moth Gu" on the plank road: those firefly-like insect swarms turn into moths and gnaw bones when encountering living creatures; and the underground palace under the coffin hides the horrifying truth that Xiangxi Wang Tan used living people to refine "immortal figurines" - the so-called "immortality elixir" is actually a "corpse bacteria culture tank" that can infect all living things.
When Aman, a Tujia girl wearing a Nuo opera mask, joins in, the three gradually reveal the secrets guarded by the tomb-keepers for generations: the hanging coffin is not a burial place, but a seal; Nuo opera is not a sacrifice, but a soul-soothing one. As the three layers of curses of the "Inverted Pyramid Underground Palace" (the sky formation of sand scorpions, the earth formation of blood corpses, and the human formation of living poisons) unfolded, Lao Jiu finally understood: The sentence "Those who move the coffin will die" left by Hu Bayi were never a warning, but a prophecy...
