Ring 0: Birthday

In the present, a schoolgirl calls her friend to tell her about how she watched the cursed videotape. She also recounts about how she experienced a nightmare, where she witnessed Sadako being murdered by Dr. Ikuma. Thirty years ago, Akiko Miyaji, the fiancé of a fellow reporter who was killed during Shizuko's infamous ESP demonstration, interviews Sadako's former elementary school teacher Sudo about Sadako's nensha powers. Sudo recounts how Sadako was withdrawn as a child and predicted her classmates drowning in the ocean during a field trip. Meanwhile, a 19-year-old Sadako joins an acting troupe as an understudy as a therapy to her nightmares suggested by her doctor. Sadako has natural beauty and charisma for the play, infuriating her senior, Aiko Hazuki, whose relationship with the troupe director, Yusaku Shigemori, sours due to the latter's newfound favor for the young trainee. Aiko is later found murdered by a figure in white, thus Sadako takes her place for the upcoming play as the lead character. Sadako attracts and reciprocates the attention of the troupe sound director, Hiroshi Toyama, much to the disappointment of costume designer and Toyama's girlfriend, Etsuko Tachihara. While praised by Shigemori and Toyama, other troupe members grow to distrust and fear Sadako, as they suspect that she is the one who caused Aiko's death and other supernatural occurrences, including strange dreams pertaining to a well and an apparition of a girl in white with long hair very similar to Sadako.

Meanwhile, Akiko is told by Sudo that though initially pleasant, Shizuko descended to madness before her suicide ever since her moving to live with Dr. Heihachiro Ikuma, and that Sudo heard strange childlike noises in the attic. Etsuko, wanting to discover Sadako's origins, contacts Sadako's psychiatrist, but he refuses to answer and throws away Sadako's résumé; the résumé is taken by Akiko's assistant, allowing him and Akiko to locate Sadako in the troupe. When they start to photograph her, she telekinetically breaks the camera; the two later discover that all photographs contain ghostly faces and a girl with long hair, confirming Akiko's suspicion of the existence of "two" Sadakos. Shigemori, having been obsessed with Sadako, says that he knows of her dark past and tells that he will kill her if she tries to kill him so they could be together. However, Toyama interrupts the process and Shigemori is killed through a cut that also wounds Toyama. However, Sadako manages to heal him just by touching him and later is able to make a disabled man regain his ability to walk. The two confess their love for each other and promise to leave the troupe and live together after finishing their last play.

The play is a disaster as Sadako, influenced by recordings of her mother's demonstration played by Etsuko, sees visions of her mother and other reporters during the demonstration and kills her psychiatrist. The troupe members, except Toyama, beat her to death, though is informed by Akiko that their job is not yet done. They visit Ikuma who tells them that Sadako, once a single individual, split into two beings resembling each of her parents; the malevolent one who resembled her unknown father is kept from growing by Ikuma in the attic. Before they can kill it, both Sadakos merge with each other and escape with Toyama. In her merged form, Sadako kills all the troupe members, including Toyama. Akiko and Etsuko manage to flee and hide in Ikuma's house but Sadako corners them and forces Akiko to shoot Etsuko before forcing her to shoot herself.

Sadako eventually recovers and tearfully mourns her own actions. However, Ikuma drugs and chases her to a nearby well. Despite her pleas, he brains her with the axe and throws her down the well before breaking down sobbing. Sadako briefly has a dream of meeting with Toyama again before she realizes she is still trapped in the well. She looks up and screams as the well stone is slid to its place, trapping her inside.

In 1999, Koji Suzuki was finishing his written sources for the Ring series by including a fourth titled Birthday which collects three short stories that filled in details of the story.[2] Asmik Ace decided to hire Ring and Ring 2 screenwriter Hiroshi Takahashi to adapt the story Lemonheart from Birthday.[2] Birthday captured the life of the character of Sadako just before she consigned to her fate seen in the later Ring series.[2] Producer Takasige Ichise offered Hideo Nakata the chance to direct, who passed on the offer.[2]

The director for the film was Norio Tsuruta.[2] Tsuruta had previously worked on direct-to-video horror scripts such as Honto ni atta kowai hanashi (Scary True Stories) in 1991, and wrote and directed the sequel.[3] After working on various television and direct-to-video works, Tsuruta got to work with screenwriter Hiroshi Takahashi on the segment "The Curse" on the television special Haunted School F.[3] Takahashi lobbied for Tsuruta to take on the film.[3] Tsuruta referred to the film as "a tragedy" with a theme about "a young woman who is oppressed because she is different from everyone else. In Japan, there is great pressure not to stray too far from the norm."[4]

Yukie Nakama was cast in the role of Sadako.[5] After Nakama's friends had seen Ring, they teased her about her resemblance to Sadako.[5] Nakama was later contacted by her agent who mentioned they were looking for actresses for the role of Sadako and tried out for the role.[5] She received confirmation of her role in the next two weeks.[5]

Ring 0: Birthday was released in Japan on January 22, 2000 where it was distributed by Toho.[1] It was released on a double bill with the film Isola.[6] The film was released direct-to-video in the United States under the title Ringu 0 on August 23, 2005 by DreamWorks/Universal Home Video.[1]

Online film database AllMovie gave the film two stars out of five, referring to it as a "mediocre Carrie rip" and that it "can only be truly reviled as a desecration of the original Ringu's uniquely persuasive and subtle horror." The review noted that the "film's effort to explain exactly who Sadako (Yukie Nakama) is and how she became a powerful evil force, the film heaps contrivance upon contrivance, mixing clichés from backstage melodramas with those from Carrie and all its imitators, and leaving the viewer with little beyond the strength of Nakama's appealing performance and a few mild scares to hang on to."[7]

• List of horror films of 2000
• List of Japanese films of 2000

• Ring 0: Birthday at IMDb
• Ringu 0 at Rotten Tomatoes