In 2015, in Seoul, a young girl named Young-shin began experiencing terrifying, inexplicable phenomena after a hit-and-run accident. Desperate for answers, renegade priest Father Kim (KIM Yoon-seok), long shunned by the church for his unorthodox methods, takes on one final exorcism. He enlists Deacon Choi (GANG Dong-won), who secretly reports to the church. As they enter Young-shin’s room, the ritual begins—a battle for survival against an unspeakable evil.