Dead Friend

Plot

Three high school girls are bored while studying for their test the next day, so they decide to conduct a séance with a bunshinsaba - a traditional Korean ouija board. As the spirit is called by Eun-jung (Lee Yoon-ji), her sister, Eun-seo (Jeon Hye-bin), wakes up screaming. Eun-seo goes to her sister's room and scolds the girls for doing the séance rather than studying. Before going to sleep, Eun-jung jokingly wishes that the ghost had taken Eun-seo away and that if they do not send the ghost away, it will kill them. The girls are unaware as Eun-seo is killed by a ghostly-water presence in the kitchen.

After a visit to her doctor, the amnesiac Min Ji-won (Kim Ha-neul), who is an expert swimmer, is told there is a high chance that she may regain her memories back. She tells her former boyfriend, Park Jun-ho (Ryu Jin), whom she does not remember since her losing her memories, that she will leave college and her mother (Kim Hae-sook) to go overseas and find a new life. However, Ji-won begins to have nightmares of a ghost from her forgotten past, which seems to be connected to water and which soon manifests itself in reality. She is confronted by an estranged friend, Yu-jung (Jeon Hee-ju), who tells her of Eun-seo's death and that because of Ji-won's action in the past, "Su-in" is coming for them. Yu-jung is soon found dead right after her meeting with Ji-won.

Ji-won slowly remembers that she used to lead an elitist clique back in high school which consisted of herself, Eun-seo, Yu-jung, and Mi-kyung. Before she became part of the clique, Ji-won was friends with Su-in (Nam Sang-mi), but her ego turned her to regard the introverted Su-in as a laughing stock while still pretending to be her friend. Ji-won visits her last remaining clique member, Mi-kyung (Shin Yi), who is confined to a mental hospital, but the latter lashes out at Ji-won for bringing Su-in back. Ji-won learns from Su-in's mother (Choi Ran) that the event that led to her amnesia was a trip to a forest with her clique and Su-in, from which Su-in never came back. She races to save Mi-kyung but is too late to stop her from being drowned to death by the ghost.

Heading to a spring in the forest, Ji-won remembers the full event: Ji-won asks Su-in if she can swim, then pushes her into the spring. Su-in comes up and all four girls gather and laugh. The three girls then push Ji-won into the spring as a joke, but upon learning that she could not swim, Su-in dived to save her. While Ji-won was saved, Su-in herself got stuck in the riverbed and drowned. The other three girls just watch as this happens. With her body not decomposing due to the chemicals in the water. Ji-won alerts the authorities and informs Su-in's grieving mother of the fact.

Thinking everything have ended, Ji-won returns to her mother, only to realize the horrifying truth: Ji-won and Su-in had swapped bodies during their struggle to get out of the spring. "Ji-won" did not lose her memories because she has never been Ji-won in the first place; she is actually Su-in. Ji-won's spirit has been terrorizing her and the clique to regain her body back, and now she inhabits her mother. Her mother then starts to vomit up water and collapses and everything seems to end. But then Ji-won crawls from the water to get her body back. Su-in manages to grab a broken vase to and uses it to cut her wrist so Ji-won can't have it. Ji-won's boyfriend, Jun-ho, hears Ji-won scream and comes in to save Ji-won and her mother. They are then rushed to the hospital. Su-in is later seen walking through the fish market where her mother, who believes her daughter had died, works. She leaves the market after hesitating for a while, while her mother looks ominously at her, with Ji-wom's tell-tale smirk, implying that Ji-won is still attempting to regain her body by possessing Su-in's mother.

Cast