The Grudge Backstory
A powerful and vengeful onryo, Kayako Saeki was the wife and mother who was brutally killed by her husband Takeo who also killed their son Toshio Saeki.
Kawamata Nakagawa was Kayako Saeki’s mother, Toshio Saeki's maternal grandmother, and Takeo Saeki's ex-mother-in-law. When Kayako was a little girl, Nakagawa was an exorcist and fed the blood of demons to Kayako, which scarred Kayako for life. When Kayako was older she became married with Takeo Saeki and both had a child together named Toshio Saeki. Kayako had a beautiful family and she also wanted to go to college which she did.
Kayako becomes obsessed with Peter Kirk, an American college professor in Tokyo Japan , and writes about her feelings for him in a diary.
Takeo finds the diary and becomes enraged, attacking Kayako as she tries to escape in fear of Takeo’s rage causing her trip and break her ankle. Kayako was helpless as she crawls for her life trying to flee away but Takeo had the advantage and snapping her neck causing kayako with a broken neck, unable to breathe as she tries to call out for help but instead her voicebox was like a rattle noise as she slowly dies in pain
Takeo also kills their son Toshio who appears on the second stairway floor as he witnesses Takeo killing Kayako and Takeo sees him as he goes upstairs to kill Toshio which he drowns him in a bathtub and kills their pet cat, Mar, and hides the bodies in their house into the attic.
As he hide the bodies Takeo began to commit suicide as some say he hunged himself. But right after Kayako and Toshio is killed Kayako’s spirit began to form as she transitions into a deadly rage onryo who kills Takeo by hanging him with the wrath of her hair as revenge of her death.
Kayako's ghost haunts the house, along with the spirit of Toshio, and kills anyone who enters the home. Kayako transforms into an onryō, a wrathful ghost who seeks revenge on the living. Those who come into contact with the house or with someone who has been cursed may experience symptoms such as hysteria, hallucinations, fever, and visions of a ghostly white naked cat-boy. The curse is contagious, and those who come contact with the house or anyone who is cursed that they have been around with will suffer their fate in the wrath of Kayako and Toshio.