Shen Jinghong, a "green-shirted guest" with special skills, went to the western border to find his old friend and seek evidence in order to clear up the suspicions in the old case. While passing through the dangerous Luomapo, he was intercepted by a masked man who came under the orders of "Hanyue Louzhu", who actually asked for the "Mountain and River Map" which he had never heard of.
In the midst of the chaos, Su Muyan, a girl in red carrying a sachet embroidered with miniature pictures of mountains and rivers, accidentally broke in, exposing the masked man's true goal. After a fight, the masked man took poison to silence him, and the clues were interrupted. Not only did Shen Jinghong fail to solve the old case, but he was involved in the mysterious storm of the "Mountain and River Map". The danger of the trip to the western border was far more dangerous than he expected, and a bigger conspiracy was quietly unfolding.
