Su Qingge, a wandering orphan girl, was adopted by the "Skylark Theater" in Chang'an. Under the troupe's special training of "using drama as the plot and mystery as the connection", she grew up to be a "drama detective" who is good at solving strange cases. By deciphering the "mystery in the play" task issued by the mysterious "Jiu Yao Pavilion" in Chang'an City (disguising the case as a drama puzzle), she gradually deepened her knowledge from small cases in the city to the secrets of the court. When she revealed the conspiracy of "Jiu Yao Pavilion" to use cases to control people's hearts, she joined forces with the hidden secret guard Xie Chenzhou, and finally disintegrated the forces behind the scenes and solved the mystery of her own life experience.
