It turns out that that the narrator (Ed Norton) and Tyler (Brad Pitt) are the same person.
The Narrator tries to stop Tyler from blowing up the buildings of various major credit card companies, but Tyler easily subdues him and brings him to the top of a building to watch the imminent explosions.
The Narrator shoots himself in the face, he barely survives but Tyler is killed in the narrator's mind; So, no more Tyler. Despite the narrator's best efforts, the buildings blow up and the narrator hooks up with Marla (Helena Bonham Carter)
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