From wikipedia:

Fight Club is a 1996 novel by Chuck Palahniuk. It follows the experiences of an unnamed protagonist struggling with insomnia. Inspired by his doctor’s exasperated remark that insomnia is not suffering, he finds relief by impersonating a seriously ill person in several support groups. Then he meets a mysterious man named Tyler Durden and establishes an underground fighting club as radical psychotherapy.[1]

Chapters are helpfully numbered 1 to 26.

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