Dark Water is a 2002 Japanese drama-horror film directed by Hideo Nakata, the director of Ring and Ring 2. Dark Water is based on Floating Water, a short story by Koji Suzuki.
Yoshimi Matsubara (Hitomi Kuroki), in the midst of a divorce, moves to a run-down apartment with her daughter, Ikuko (Rio Kanno). She enrolls her daughter in a nearby kindergarten and in order to win custody of her daughter, starts working as a proofreader, a job she held years ago before she was married. The ceiling of the apartment has a leak, which worsens on a daily basis. Matsubara complains to the janitor of the apartment, an old man, but the janitor does nothing to fix the leak. She then tries to go to the floor just above her apartment to find out the root of the leak, and discovers that the apartment is locked.
Strange events then happen repeatedly: a red bag with a bunny on the front reappears no matter how often Yoshimi tries to dispose of it. Hair is found in tap water. Yoshimi gets glimpses of a mysterious long-haired girl who is of similar age to her daughter. Yoshimi discovers that the upstairs apartment, the source of the leak, was formerly the home of a girl named Mitsuko Kawai (Mirei
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