 Why was Brandon raped and murdered?
The film opens with--literally--a surge of adrenalin, which travels through the bloodstream and into the brain of its protagonist, Jack (Edward Norton), who's viewed, as the camera pulls out of his insides, with a gun stuck in his mouth. Jack and Bob subscribe to a new form of male bonding: They cling to each other and sob. But Jack's idyll is rudely disrupted by--wouldn't you know it?--a woman. "Self-improvement," explains Tyler, "is masturbation"; self-destruction is the new way.
 He was raped and murdered after his physical gender was discovered.
 He was involved in a barroom brawl.  He was raped and murdered after his physical gender was discovered.  He was attacked after hitting on a beautiful girl in a bar.  He was attacked after surfing from the bumper of a pickup truck.