After a mundane existence in contemporary Korea, a man finds himself reincarnated as a grand prince during the Joseon Dynasty. However, his fortunes sour as he becomes the younger sibling of the infamous King Yeon-San, known for his tyrannical rule. As the kingdom braces for a dark era, Grand Prince Jin-Seong emerges as a beacon of hope, determined to steer the course of history away from oppression and chaos.