College student Heui-jin returns home when her 14-year-old sister So-jin goes missing. Her mother, a fanatic churchgoer, resorts to prayer and refuses to work with the lazy police to find So-jin. Meanwhile, a neighbor commits suicide and leaves a will for So-jin, and Heui-jin hears rumors that her sister had been possessed. The whereabouts of So-jin becomes increasingly elusive and the dead neighbor begins appearing in Heui-jin's dreams.