After he traveled the city by foot, a mathematician stuck his gaze onto the overpasses, cable-stayed bridges, and light beams randomly colliding at night. Tired of only seeing things on the ground, he decided to take off from a bridge, and hunt his “angles” while cruising through the sky.
On the birthday of the empress Wu, she suddenly encountered a five-clawed golden dragon appearing in the palace hall, and a series of mysterious incidents also occurred in the city. Di Renjie was ordered to investigate when he was in danger. He never thought that a huge conspiracy would be involved behind these mysterious incidents. Facing the crisis of life and death and national turmoil, how will Di Renjie meet the tricks and solve it easily?