What if an assassin who lost her memory while trying to assassinate the king suddenly collapsed and is then appointed as a concubine the next day?

Yeon-wol, the only survivor of the Yeon clan, who were killed as traitors, becomes an assassin while hiding her identity in order to take revenge on the king.

Yeon-wol infiltrates as a court lady and secretly seeks the king's neck, but falls into a trap set by the king and loses her mind due to the strong scent and collapses. The next day, Yeon-wol wakes up with no memories of the past, and unexpectedly receives the king's instruction and is enshrined as concubine Eunhyobi.

King Hyeonu is furious at the actions of Akhee who brought Yeonwol, an assassin who came to kill him, as one of his concubines and runs to the concubine to kill her, but she loses control of her body...

Wol Yeon of the great Yeon clan in the Kingdom of Asatae is a spirited girl who dreams of becoming a general one day. Her dreams are crushed when the royal government mercilessly eradicates her clan, murdering everyone, including Wol’s parents. Wol is left with no one she can trust but her tutor Jae-i, who proceeds to raise and train her as a master assassin so that she may take revenge against the king. Eight years later, Wol successfully infiltrates the palace to kill the king, only to find that all is not as it seems…