Veteran Chen Mo is drawn into a shocking conspiracy spanning a thousand years after his grandfather leaves him half a Warring States silk manuscript and the dying words, "Seven-Star Corpse Cocoon: Keep away, and do not covet it." Along with Qin Feng, a history whiz, and Lin Yue, an heir to the art of mechanical traps, he embarks on a perilous quest to uncover the secret of the Star-Gazing Clan's immortality.
From the corpse-cocoon tomb in the Qinling Mountains to the Mirror of Guixu in the South China Sea, from the bronze tree atop the clouds to the twin tombs in the northern desert, they go on to brave the hanging-coffin formation in Wu Gorge and cross the frozen abyss of Kunlun. The trio solve one sinister mechanism after another, forging trust amid mortal danger. Meanwhile, they must contend with the Keepers, who have guarded the secret for generations, the Heaven-Seizing faction, which seeks to claim its power, and foreign forces coveting supernatural technology.
As the truth is revealed layer by layer, they discover that immortality is nothing more than a cruel experiment that strips away the senses and humanity. The Seven-Star Observatory is no treasure, but a shackle sealing seven "inhuman" test subjects, and the trio's bloodlines have long been bound to this tragedy. At last, before the bronze gate on Changbai Mountain, they renounce the illusory power and choose to seal the truth forever, each becoming a silent guardian of history's secrets in their own way.