In the turbulent interregnum following the collapse of the Tang dynasty, a young daughter of a herbalist was tricked and sold into a brothel. After a harrowing escape from death, she eventually found herself in a city of female assassins. Assuming the new name of Wan Mei, she began to learn from ropes of being an assassin from Chang An, a young man who acted as her guide and warder.
Over time, Wan Mei and Chang An began to develop genuine affection for each other. But Cha Luo, the leader of the assassins took a dislike to Wan Mei and plotted against the couple with her cohorts. Wan Mei's personality and gifts caused Gong Zi, the hidden owner of Gui Hua City to take a interest on her. Burdened by his hidden identity, Chang An began to distance himself from Wan Mei. The protagonists found themselves embroiled in escalating conspiracies involving deadly betrayals and struggles for power.
Source - Mydramalist
This is another c-drama that i am watching via viki, its quite interesting if you are interested in watching it.