The story begins when Tyler Durden is holding a gun in the mouth of the narrator on top of a building. It is at this point that the narrator has a flashback of how things got to this point. He was an office worker but was unsatisfied with the type of life he was living. The work in the office is boring and leads him to insomnia. However, the doctor does not offer any meaningful solution and only suggest he should join support groups with people who have real problems.
The narrator heeds to this advice and pays a visit to support groups with the pretense that he has many problems. When he meets Big Bob, who had his testicles removed because of abusing steroids, their embrace makes the narrator feel better. The narrator falls asleep that day. There is also a woman, Marla Singer, who also fakes her problem to attend the support group meeting. With her presence in the meetings, the narrator no longer feels comfortable. The meetings are now meaningless to him.
Due to work commitments, the narrator now visits accident sites to determine the extent of the damages caused. He meets a man called Tyler on a visit to a nude beach. It is this man that accepts to live with the narrator when explosives blow his condominium. The narrator can no longer attend to his official work commitments. They do night jobs with Tyler and break the rules.
When Tyler asks the narrator to beat him hard, they begin engaging in a nasty fight. There is a night the narrator dreams of a sexual encounter with Marla. When the next morning, Tyler says he had sex with Marla the previous night, the story generates a bigger fight between Tyler and the narrator. There are a series of events that leads to the setting up of the mayhem. Tyler disappears to Seattle where he meets Marla. The narrator kills Tyler’s boss. This makes Tyler castrate the narrator. At last, the narrator ends up in a mental institution. That is the book by Chuck Palahniuk.