In the late Ming dynasty, Zhang Xianzhong carried a mysterious national treasure and fled into the Wanxi Grand Rift Valley, disappearing from the long river of history ever since. Four hundred years later, archaeologist Chen Mo's team accidentally discovered ancient tomb ruins during scenic area construction, but encountered a mountain collapse and became trapped deep in the heart of the mountain. In this underground labyrinth filled with mechanisms and secret passages, Chen Mo not only has to crack the layers of puzzles left by Zhang Xianzhong, but also face the test of human nature among his fellow travelers: the mysterious woman Su Man's identity is unknown, the tomb-robbing gang kills each other out of greed, and the mad Ma Biao holds a gun to coerce everyone into treasure hunting. When the truth comes to light, everyone discovers that the true treasure was never gold and silver.