One day, a mysterious letter 'F' starts to be written on doorplates in a condominium building. Since then, mysterious incidents consistently occur around Yukari Yamamoto, who is an ordinary female high school student living in the building.

When elementary school teacher Kobayashi investigates the absence of one of his young pupils from the classroom, he finds himself at the doorstep of an anonymous suburban house that harbours a horrible secret, and into which all who enter are doomed.

On his request, the sensitive sister of a real estate agent visits a house he intends to put up for sale, only to cross paths with its resident curse.

When pregnant Mia Sakaguchi falls from a staircase at the shrine, she is transferred to 1994 and immediately admitted to a mental institution, because no one believes her that she is from the future. There she is confronted with the shocking truth that the mentally ill are forcibly sterilized. In order to protect her unborn child, she tries to escape from the institution.

A young couple's announcement of their engagement to their friends is followed by a series of interactions and conflicts that forces everyone to reflect on their lives.

The day after being dumped by the boyfriend to whom she was going to give her virginity, Sawako Tsukahara (Kumiko Endo), an office lady in the accounting department of Manpan Trading Co., is dispatched as a helper to General Affairs Section 2. General Affairs Section 2, nicknamed "Shomuni," is the company's cesspool department where underachieving office ladies are gathered. The members of the General Affairs Department are Chinatsu Tsuboi (Reiko Takashima), who is in charge of the department; the femme fatale Kana Miyashita (Michiko Kawai); the self-disciplined Yumiko Maruhashi (Asako Kobayashi); the boastful Kayoko Tokunaga (Mari Hamada); the unremarkable Section Chief Inoue (Masao Komatsu); and the stray cat, Butcha.