During the serialization, the novel was at first written as a series of short stories representing chronological snapshots of the overall plot line.

In order to protect his first love, Yukiho (Ayase Haruka), the young boy Ryoji (Yamada Takayuki) accidentally killed his father; and in order to protect Ryoji from being exposed, Yukiho also killed her mother who knew the truth and put the blame on her.

In order to escape legal sanctions, the 11-year-old Ryoji and Yukiho made a promise that they would live like strangers for the next 15 years.

The investigation, headed by officer Junzo Sasagaki, gradually uncovers Fumiyo Nishimoto, a mother struggling to make ends meet and one of his customers, and her boyfriend Tadao Terasaki, as prime suspects.

The story primarily concerns itself with the effects of this incident on two people: Ryoji Kirihara, the pawnbroker's son, and Yukiho Nishimoto, Fumiyo's daughter.

Ryoji ends up growing into a moody, sullen and cynical youth who gets involved in a number of shady dealings, such as housewife prostitution rings, computer game bootlegging, hacking corporate programs, and wiretapping.

The novel strongly suggests that he commits multiple murders, including Isamu Matsuura, a former employee of his father's shop who he assists in a videogame bootlegging scheme.

Yukiho is adopted by a relative of her father's (changing her last name from Nishimoto to Karasawa) and matures into a beautiful upper-class woman, attracting the attention of multiple men and achieving success in different fields, such as stock trading and opening up a successful clothing store chain.

Throughout the story, Sasagaki shows up multiple times, unable to let go of the unresolved murder and determined to find the truth, even after the case passes the statute of limitations.

Ryoji, who was Yukiho's friend, became suspicious after seeing her with his father and followed them to an abandoned building, where he witnessed Yosuke molesting her.

In turn, Yukiho killed her mother by drugging her with sleeping pills and causing a gas leak in her house.

Ryoji and Yukiho then developed a close relationship of some sort in order to cope with their grief, using their talents to achieve success and ruthlessly disposing of anyone who got in their way.

The police wait for him to appear at the opening of Yukiho's second shop on Christmas Day, and discover he is one of the employees dressing up as Santa Claus.

He started to get involved in shady businesses like housewife prostitution rings and game bootlegging when he was a student.

Afterward Yukiho was adopted by Karasawa, received a good education, and turned into an upper-class lady with manners and elegance.

Many reviewers admired how Keigo Higashino crafted a 20-year mystery, connecting multiple characters and events in surprising ways.

[6][7] The novel has been described as a subversive and intricate psychological crime thriller, often compared to works by Stieg Larsson for its layered storytelling and long-term exploration of its characters' lives.

It renowned for its dark narrative, psychological depth, and exploration of the human capacity for both resilience and cruelty.

[15][16] The bubble economy was a period of rapid growth driven by high asset prices and speculation, leading to a widening gap between the rich and the poor.

Yukiho’s rise in society, despite her dark past, shows the ambitions and moral compromises associated with Japan's economic boom.