A modern undercover agent, Ah Ying, was killed, and his soul traveled to the body of the ninth prince Xiao Yi, who was blind and had disabled legs. He relied on Cangming's secret skills obtained through modern thinking and mystery to conceal his plans in the palace, and got to know Xiyue, who possessed the power of red eyes and was regarded by the national master Cangming as the key to the door to the ruins. At this time, a series of mysterious cases occurred in the capital, involving secrets of the previous dynasty and royal scandals. Xiao Yi and Xiyue jointly investigated and gradually uncovered a huge conspiracy to exchange power with "blood sacrifice". Cangming wants to use Xiyue as the key to draw the power of Guixu to subvert the world, but Xiao Yi discovers that his own time travel may be the key to preventing this disaster. At the same time, Jhin, who possesses the power of the stars, Lu Chen, the controller of the tidal power, Chu Lie, the general who defended the city, and many other characters are involved in this maelstrom of intrigue and sadomasochism that concerns the fate of the world. In the end, Xiao Yi must make a cruel choice between preserving his love and stabilizing the current situation.
