Si Zuxian has not been interested in war since he was a child, and likes to knit clothes and design clothes. However, his father Si Zusheng (played by Kim Taewoo) is disgusted with this behavior and thinks that he should look like a man on the battlefield.Admired by others.

In order to educate his son, the greedy Si Zusheng planned a rebellion and forced Si Zuxian to the residence of General Yanfengxue (played by Oh Ji-ho) to overthrow Wang Zheng in front of him.After the collapse of the Yanshi Dynasty, Sizusheng naturally ascended to the throne and became the king, Sizuxian was also promoted to the crown prince, and Yanyue (played by Hong Yeji), the daughter of the former general, became the only survivor of the Yanshi dynasty.

Ten years later, Yanyue always planned revenge. Now she has become an excellent assassin, usually carrying out tasks in the name of Guila. In order to get closer to the royal family, she also practiced dancing diligently and became a court dancer with first-class dancing skills..One day, Yanyue visited a tailor shop in the city because her clothes were inconvenient. She fell from the roof and found that the clothes maker was actually an uncle, Si Zuxian.

Facing the rude Yanyue, Sizuxian decided that she was not qualified to wear the clothes she had sewn. Not only did she not want to help her modify her needs, she even wanted to recycle the clothes themselves.Yanyue felt that Sizuxian was unreasonable, but after learning that he dreamed of becoming a tailor but was opposed by his father, he encouraged him to bravely defend what he wanted to do. Sizuxian was moved by Yanyue's words because of this.This was the first time someone said that to him.

Back at the palace, Si Zuxian was still belittled for failing to show the character a prince should have. His father, Si Zusheng, in disguise, expected him to do well in tomorrow's hunt.Back in his dormitory, his attendants advised him not to fall asleep, otherwise his other personality, Ergui, would take over his body.The next day, Sizuxian abnormally showed off his kung fu on the hunting ground, and thus won Sizusheng's approval. In fact, it was Ergui's personality that took over the body.

Later, Ergui went to participate in the street competition, and Yue Feng, who was dominating the field, was defeated within a few moments.During the competition, Ergui accidentally discovered that Yuefeng under the veil was actually a girl, so he chased after her after she left the competition ground.Ergui asked Yue Feng to let him see his true face, but Yue Feng did not agree and instead destroyed his mask. Although only half of his face was exposed, Yue Feng quickly recognized him as the uncle from the tailor shop.Yes, Yuefeng is another pseudonym of Yanyue.

Yanyue told Ergui that the first meeting between the two was quite pleasant, but now he seems to be a different person, like a fake who looks exactly the same.It was the first time that Ergui heard someone praise Sizuxian's personality, so he repeatedly confirmed with her how Sizuxian could compare with him.At this time, Ergui had realized that he was gradually falling in love with Yanyue.

One day after that, Yanyue and her assassins planned to launch an attack on the king. Yanyue once again joined the group of dancing girls, hoping that Sizusheng would choose her to spend the night together, so that she would have a chance to be alone and attack him.However, Sizusheng finally chose another dancer, which forced Yanyue to change her plan. When she was taking a bath in the bathtub, she was about to attack the king behind her. Unexpectedly, Yanyue turned around and appeared in front of her.The person is evil