Crown Prince Evren triggers the ancient mirror's "Trial of Truth" during the succession rite before his coronation. Every lie he speaks against his true will causes his body to grow beyond his 190-centimeter frame and gradually transform into a beast—sprouting black scales, slit pupils, and horns—and only admitting his genuine desires can reverse the change. If he cannot regain his human form within seven days, he will forfeit his right to the throne. Liora, a laundry and alteration maid, accidentally enters the sealed Old Palace, stumbles upon the transformed Crown Prince, and is drawn into the trial. Amid the repeated tug-of-war between lies and confessions, Evren must confront his mother's control, the pressure of a political engagement, and the choice his heart truly wants.
