Accept it if you want to live." A tragic orphan, 'Yoo-hee,' succumbs to a rare disease at a young age. Despite a life full of misfortune, she fought desperately to survive. On her deathbed, the drama Chasan-gun is playing on the screen. Just when it seems like she’s passed away, Yoo-hee's soul finds itself inhabiting the body of a mad maid, and she is thrust into the historical world of Chasan-gun. The tyrant, Chasan-gun Lee Yoon, is infamous in history for his brutal reign. Was he truly just a villainous ruler, the 'waste of history'? Amid a time of indulgence and luxury, in an era full of hidden truths, Yoo-hee’s involvement changes the course of Joseon's history.