Ring (Japanese: リング, Hepburn: Ringu) is a 1998 Japanese supernatural psychological horror film directed by Hideo Nakata and written by Hiroshi Takahashi, based on the 1991 novel by Koji Suzuki. The film stars Nanako Matsushima, Miki Nakatani, and Hiroyuki Sanada, and follows a reporter who is racing to investigate the mystery behind a cursed video tape; whoever watches the tape dies seven days after doing so. The film is also titled The Ring (stylized as the Ring) in Japan and was released in North America as Ringu.

Production took approximately nine months, and the film was shot back-to-back with a sequel, Spiral, featuring much of the same cast but involving neither Nakata nor Takahashi; both films were released together in Japan on January 31, 1998, with the studio hoping for the popularity of the novel to make both films successful. After its release, Ring was a box office hit in Japan and internationally and was acclaimed by critics, who praised its atmosphere, slow-paced horror and themes.

Spawning a popular franchise, the film has been highly influential, triggering both a western popularization of Japanese horror, including with its own English-language adaptations starting with 2002's The Ring, and a renaissance of Japanese horror films, inspiring other successful franchises such as Ju-On and The Grudge and spearheading Hollywood's horror films' transition from slashers into more atmospheric films in the 2000s. Despite the success of the original film, Spiral was largely ignored upon release, leading to Nakata and Takahashi making Ring 2 (1999), another sequel ignoring the events of Spiral.

During a sleepover, high schoolers Tomoko and Masami discuss an urban legend about a videotape that curses its viewers to die in seven days after a foreboding phone call. Tomoko then confesses that last week, she and her friends watched a strange videotape and received an inexplicable phone call. After a false alarm phone call, Masami goes to the toilet. Tomoko witnesses the TV turn on by itself and is killed by an unseen figure.

Reiko Asakawa, Tomoko's aunt and a journalist investigating this urban legend, attends her funeral and learns that three of Tomoko's friends who watched the tape with her all died at the same time. Reiko finds an unmarked videotape in a resort cabin in Izu where the four stayed. It contains brief, seemingly unrelated scenes accompanied by screeching sounds, and ends with a shot of a well. After watching, Reiko sees an apparition and receives a phone call emitting the screeching sounds from the tape. Convinced she has been cursed, Reiko takes the tape and leaves the cabin.

Reiko enlists the help of her psychic ex-husband Ryūji Takayama. Examining a copy of the tape that Reiko made, the pair find a cryptic message spoken in an Ōshima dialect, and prepare to go to Ōshima. Before departing, Reiko catches Yōichi, her son with Ryūji, watching the tape after being pressured by "Tomoko."

In Ōshima, Reiko and Ryūji learn about Shizuko Yamamura, the woman on the tape. Before her suicide, Shizuko gained notoriety following a public demonstration of her psychic ability organized by ESP researcher Dr. Heihachiro Ikuma, with whom she had an affair. When confronting Shizuko's cousin Takashi, they learn through a vision that during the demonstration, Shizuko's young daughter Sadako psychically killed a journalist who decried Shizuko's abilities. After failing to track down Sadako, Reiko realizes that Ryūji never received a phone call after watching the tape, as she did at the cabin in Izu. They rush back to the cabin.

Reiko and Ryūji find a sealed well in the cabin's crawlspace. Through another vision, they learn that Dr. Ikuma trapped Sadako inside the well. They conclude that Sadako remained alive and that the curse was born when a videotape "recorded" the rage she had projected. They drain the water and find Sadako's remains. Reiko's seven-day deadline passes and she remains alive, leading them to believe the curse is broken.