During a chaotic period towards the end of the Tang Dynasty, Qi Xue (Li Yi Tong) was sold to a brothel by her own father. She gets a second chance after inadvertently entering a mysterious city where she was given the name Wan Mei. Tasked with dangerous missions, she risks her life time and again but gains the protection of Chang An (Qu Chu Xiao) who is a man that lives like a shadow. The two become embroiled in a greater conspiracy involving a deadly struggle for power.
