A young woman searching for a lost child comes to suspect more than abduction is involved in this horror story from South Korea. Kang Heui-jin (Nam Sang-mi) is a college student who often argues with her mother (Kim Bo-yeon) about religion -- Heui-jin doesn't acknowledge the existence of a supreme being, while her mother is a devout Christian who fears for her soul. When Heui-jin receives word that her 13-year-old sister, So-jin (Shim Eun-gyeong), has gone missing, she comes home to help look for her, even though she's still shaking off an illness. Mother and her friends are certain So-jin has been possessed by the devil, and while Heui-jin thinks this is absurd, she's even more upset by the way the investigating police officer, Tae-hwan (Ryoo Seung-ryong), treats such notions; Tae-hwan is impressed with Heui-jin's tenacity when she gives him a piece of her mind, and together they set out to find the missing child. However, as they interview a number of different neighbors about the disappearance, all of whom have different spiritual views, a strange pattern develops and their suspicions grow when one of So-jin's best friends is found murdered. Bool-sin-ji-ok (aka Possessed) was the first feature film from writer and director Lee Yong-ju, who was previously an assistant to South Korean horror auteur Bong Joon-ho.
by Mark Deming synopsis