Journalist Kazuyuki Asakawa investigates the mysterious simultaneous deaths of four high school students, all of whom suffered heart attacks despite being young and healthy. His inquiry leads him to a remote mountain cabin where the teenagers had stayed one week before their deaths. There, he discovers a videotape and watches it, only to find it contains nothing more sinister than a pop music video by singer Nao Matsuzaki. However, when another man who viewed the same tape dies of a heart attack exactly two weeks later, Asakawa realizes he has only thirteen days to solve the mystery before suffering the same fate.

Unlike the more widely known film adaptations, this twelve-episode Fuji TV series blends the cursed videotape premise with a biological interpretation of the curse. Asakawa seeks help from Ryuji Takayama, a twenty-four-year-old cultural anthropologist with a mysterious past and ambiguous motives who specializes in paranormal phenomena. Together they analyze the tape using computerized digital methods and uncover its supernatural origins. The investigation is further aided by Yoshino Akiko, a fellow journalist who becomes Asakawas primary partner and potential love interest, and Miyashita Rieko, a medical university professor who brings a scientific perspective to the case.

The series expands significantly on the source material, incorporating elements from both Koji Suzuki's original novel and Hideo Nakata's 1998 film while introducing new plotlines. As the investigation progresses, the characters uncover the tragic story of Sadako Yamamura, a young woman with supernatural powers who was thrown into a well and left to die decades earlier. Her vengeful spirit manifests through the videotape, but the series also explores the curse as a mutating virus-like phenomenon. The narrative follows Asakawa and his allies as they race against time to understand Sadakos history and find a way to break the curse before the thirteen days expire.

Major narrative arcs include the discovery of Sadakos connection to a theater troupe, the involvement of Doctor Nagao Joutaro who confesses to her murder, and the emergence of new supernatural abilities in those who view the tape. Episode titles chart the escalating crisis, from The Seal is Now Solved through Sadakos Revival and ultimately to the revelation that the curse was not lifted, with a new dead person threatening to destroy the world. Ryuji Takayama meets his end in episode eleven, dramatically altering the dynamics of the investigation. The series aired on Fuji TV from January 7 to March 25, 1999, and was followed by a sequel series titled Rasen.