To keep the mood on the set light, the actors and director would often joke around and attempt to frighten one another. This included a Karaoke session performed by Shimizu, Takashi on Kebbel, Arielle's birthday.
On the "Columbia" logo screen before the feature, the standard logo appears normal for a moment, then the hair grows and the Columbia statuette turns to Kayako as the word "Columbia" changes to "Grudge 2". The screen flashes for a moment as this happens.
Director Takashi Shimizu went to Los Angeles to meet with producers Rob Tapert and Sam Raimi in a small office at Columbia Pictures. The purpose was to develop a story outline for the sequel's first draft, which also involved employees from Tapert and Raimi's production company Ghost House Pictures, producer Taka Ichise, and writer Stephen Susco. According to Tapert, the session was roughly seven or eight hours of people suggesting ideas for the story.
The first film omitted the subplot involving the three schoolgirls which was present in the original Ju-on: The Grudge (2002). The subplot was resurrected for this film (Misako Uno's character is even named Miyuki just like one of the girls in the original film).
The trivia item below may give away important plot points.
In the original Ju-on: The Grudge (2002), Rika (Megumi Okina) actually dies at the film's conclusion by the hands of Takeo Saeki. The ending was drastically changed for this film's predecessor in which Karen survives (she does however die in this film) though it was restored for this film although the circumstances surrounding Aubrey's death occured differently.