Brad Pitt gained more popularity in the '90s when he took the lead in David Fincher's masterful 1999 cult-classic "Fight Club."

At first glance, "Fight Club" seemed to be an ordinary movie that never had its ups and downs. The psychological thriller focused on modern masculinity, but many things happened on the set that not everyone probably knows until now.

Brad Pitt's Explosive Recipe Is Not True

In one of the most interesting scenes in the movie, Tyler Durden, Pitt's character, narrated how a person can easily make homemade explosives. The original script contained real instructions, but since the film is a "Brad Pitt Film," the producers expected that a lot of people would watch it.

To avoid people from actually copying the recipe and creating homemade explosives at home, the "Fight Club" makers changed it. They added a recipe that was not really included in the actual explosive recipe from the book.

Reese Witherspoon Was The First Choice For Marla Singer's Role

Marla Singer's role did not originally belong to Helena Bonham Carter, even though Director Fincher always favored her.

During the "Fight Club" pre-production, they put Winona Ryder and Courtney Love under consideration. However, the studio insisted on casting Reese Witherspoon.

However, the actress refused to accept the role and she never personally revealed the reason why.

According to a post on CafeMom's website, Witherspoon found Marla Singer's role as "too dark," which was reportedly the reason why she turned down the offer.

Brad Pitt's Broken Tooth Was REAL

Brad Pitt's "Fight Club" film is based on the novel of award-winning writer Chuck Palahniuk, and Pitt convinced himself to give justice to his character when he landed the lead role.

To make the film more interesting, Pitt showed his dedication by chipping his teeth for his role.

According to Cindy Guagenti, Pitt's publicist at the time, the "Once Upon a Time In Hollywood" actor was willing to give up his teeth in order to create a more authentic appearance.

Pitt reportedly said that it was no big deal to return to the dentist once the filming was done to get the "damage" fixed.

"Brad's willing to go to great lengths for a character," Cindy said. "Most people hate to go to the dentist."

Later on, Guagenti confirmed that when the filming had finished at the end of October, Pitt got his pearly whites restored.

Aside from sacrificing his teeth, the actor also took classes for his role, including soap-making classes, boxing, and taekwondo.

Pitt's fans continue to applaud his performance in "Fight Club" even years later because of his professionalism and dedication.

"Won't watch MMA, but man Fight Club is about waaaaay more than a bunch of dudes swinging on each other in a dirty warehouse," one fan said. "you have to see it at least once. Helena Bonham Carter is awesome. the story is awesome. Brad Pitt is Brad Pitt with busted teeth. A+++"

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