Thrown into the unforgiving world of 15th century Joseon, Seo-jun must rely on his knowledge of history to survive, but every attempt to change the course of events is met with unexpected resistance. As he navigates the treacherous landscape of royal courts and ancient traditions, he begins to realize that his presence in the past may be more than just a coincidence. Can he find a way to return to his own time, or will the weight of history’s resistance crush him? As the shadows of the past close in, Seo-jun’s greatest challenge may be unraveling the mystery of his own presence in a bygone era.