Modern gold-medal assassin Yun Mo transmigrated into a woman of the same name after death. Since childhood, the original owner was disguised as a man by her mother just to gain a foothold in the Yun family, and ultimately died amid identity struggles. After arriving, Yun Mo only wanted to run away with her mother and shake off the danger of being exposed at any moment. Before she even made a move, she was targeted by Jin Cang, the uniquely powerful and capricious Prince of the Great Yuan Dynasty, and brought back to his estate. From then on, in order to stay alive, she began a battle of wits and courage with this gloomy prince. An assassin's vigilance and the secret of being a woman are walking on thin ice right under Jin Cang's nose.