Two teenagers, Masami (Hitomi Sato) and Tomoko (Yuko Takeuchi) talk about a videotape recorded by a boy in Izu which is fabled to bear a curse that kills the viewer seven days after watching. Tomoko then reveals that a week ago, she and three of her friends watched a weird tape and received a call after watching it. Unnervingly similar to the storied videotape, Masami realizes that Tomoko was fated to die. After some unsettling moments, Tomoko is killed by an unseen force with Masami having the horror of watching.
Some days later, Asakawa Reiko (Nanako Matsushima), a reporter investigating the popularity of the video curse among teenagers, discovers that her niece, Tomoko and her three other friends mysteriously died at the same time on the same night with their faces twisted in a rictus of fear. She also discovers that Masami, the girl who was with Tomoko when she died, went crazy and is now in a mental hospital. After stumbling upon Tomoko's photos from the past week, Reiko finds out that the four teenagers stayed in a rental cabin in Izu. Eventually, she flips to a photo of the teens with their faces blurred and distorted.
Later, Reiko goes to Izu and finds an unlabeled tape in the reception room of the rental cottage where the teenagers stayed. Watching the tape inside Cabin B4, Reiko sees the tape containing a series of seemingly unrelated disturbing images. As soon as the tape is over, Reiko receives a phone call, a realization of the tell-tale videotape curse. Then on, she now assumes that she has a week to live. On the first day, Reiko enlists the help of her ex-husband, Ryuji Takayama (Hiroyuki Sanada). They take a picture of Reiko and find her face blurred in the photograph, further confirming that Reiko really was cursed. Ryuji then watches the tape, against Reiko's objections. A day later, Reiko creates a copy for Ryuji for them to study. They find a hidden message embedded within the tape saying that "if you keep on doing 'shoumon', the 'boukon' will come for you." The message is in a form of dialect from Izu Oshima Island. The two sail for Oshima (after Asakawa's son watches the videotape) and discover the history of the great psychic Shizuko Yamamura.
With only a day left, Reiko and Ryuji discovered that Shizuko's lost daughter, Sadako, must have made the videotape. Determined, the two go back to Izu with the assumption that Sadako is dead and it was her vengeful spirit that killed the teenagers. The duo then uncover a well under Cabin B4 and realize, through a vision, that Sadako's father killed her and threw her into the well. They try to empty the well and find Sadako's body in an attempt to appease her spirit. Reiko finds Sadako's body. When nothing happens to her, they believe that the curse is broken.
All seems fine until the next day when Ryuji is at his home and his tv switches on by itself showing the image of a well. He stares in horror as the ghost of Sadako crawls out of the well and out of Ryuji's TV set and kills him. Desperate to find a cure to save her son, Reiko realized what she did that Ryuji did not, thus saving her: She copied the tape and showed it to him. With a VCR and Ryuji's copy of the tape, Reiko rides to her son in attempt to save him, realizing that this is a never-ending cycle: The tape must always be copied and passed on to ensure the survival of the viewers.