In a fictional kingdom haunted by strange and terrifying events, the king secretly summons Gu Cheon, a proud and powerful ghost-slayer who can transform into a spirit and traverse the spectral realm, and Saeng Gang, a court lady cursed with the ability to hear and communicate with the dead. Tasked with investigating a sinister force lurking within the Crown Prince's East Palace, the unlikely pair uncover long-buried secrets hidden behind the royal walls. As they venture deeper into a world where the living and the dead intertwine, they must confront vengeful spirits, dark conspiracies, and an unimaginable evil that threatens the palace from within.