David Fincher's Fight Club is a late '90s classic that's gained its full audience over time. Part of the reason for its success is the character of Tyler Durden (Brad Pitt).

RELATED: 10 Movies That Are Unofficial Remakes Of Taxi Driver

Pitt brings one of his best performances to date to the table, and his energy makes it easy to forget that it's all illusion. Even those who've missed Fight Club thus far know the ending, and they'd probably be able to spot small hints throughout the film's runtime, as could any eagle-eyed viewer.

Tyler Durden At The Doc's & Grief Counseling Group

Tyler Durden holding a bar of soap in the movie Fight Club.

Tyler Durden (in his various forms) is nothing short of a quote machine. Fight Club's morbid humor has led to many of his lines being spouted like scripture throughout the 20 years following its release.

Before The Narrator himself outwardly desires to "destroy something beautiful," Durden plants the thought in his head, so to speak. Durden starts popping up in random places very early in the movie's runtime, including in a doctor's office prior to the "two" characters even meeting one another. But Durden's devil-may-care attitude is beginning to consume the narrative (and The Narrator) regardless.

Only One Ticket To Ride

Edward Norton and Brad Pitt riding on a bus in Fight Club

Once The Narrator and Tyler Durden begin fight club, they become inseparable. The point when it starts to turn to malice is on the bus. Durden goes in on the difference in merit between self-improvement and self-destruction. When mentioning self-destruction, he gets a gleam in his eye that would be hard to replace if Fight Club was released today.

But The Narrator is really on that bus having a conversation with himself. When he and Durden first board, only the latter tosses in his change for the fare.

Not So Much A Stranger

A still of the Narrator and Marla at a restaurant in the 1999 movie Fight Club, with a bruised waiter standing next to them

"I know this because Tyler knows this" is one of the first lines spouted by The Narrator in Fight Club, and it's extremely prescient in of discerning identity.

RELATED: 10 Movies That Subtly Spoil The Ending Early On

It also extends to those who know Tyler, because they also seem to know The Narrator equally well. There's a bruised bartender who definitely calls The Narrator Tyler, while there's a server at a local restaurant who brings Marla and The Narrator a free dish, offering not-so-subtle clues that he's well aware of the existence of fight club (which has a rulebook mostly consisting of: "Don't talk about fight club").

Odd Flashes Of That First Fight

Tyler walking around outside in Fight Club

Fight Club may have one of the most memorable final shots from '90s movies, but it's a scene relatively early in the film that proves the most important.

The "I want you to hit me as hard as you can" scene is outright iconic, but it's also the most oft-revisited one in the film. The Narrator is, of course, hitting himself. Flashes of this initial bout with violence appear sporadically throughout the film, particularly in other violent key moments.

Durden's An Actor?

Brad Pitt in Fight Club

Prior to The Narrator officially meeting Durden on the plane, he gets glimpses of the alter-ego. Very early in the film, when he's informing the audience about his views of insomnia, a commercial appears on the TV.

RELATED: 10 Things About Fight Club That Still Hold Up Today

There's a team of waiters holding out their hands in a welcoming manner. To the far right is Durden. The movie does establish that Durden has a job as a waiter at a high-class restaurant, but it's never established that he has any acting credits.

The Car Alarms

Tyler Durden and the narrator talk in the "I want you to hit me as hard as you can" scene in Fight Club

The escalation of chaos is a major throughline in Fight Club, and it could be one reason why it's a great film that was a box-office flop. Before Durden is conspiring to blow up a city block, though, he's smashing cars.

Durden and The Narrator take baseball bats out to the street and slam them into the vehicle's hoods and lights. However, only The Narrator's blows result in the ringing of car alarms. Each one of Durden's swings results in silence because only one person is even there to swing the bat.

Fight Clubs All Over The Country...As Long As The Narrator Is There Too

Brad Pitt wearing sunglasses on a plane in Fight Club

Project Mayhem is the end result of the fight club's popularity. It's also the protagonist getting his fill of one outlet, and moving on to the next.

The Narrator tells the viewer that, seemingly no matter where he traveled (typically to find out if a vehicle recall is required) fight clubs soon began to appear. It was becoming a countrywide phenomenon, if not also a quiet one because he's traveling to these different locations. The coincidence is a lie, even if he fails to realize it.

The Insomnia Line

Tyler Durden sitting in a hotel room in Fight Club

Fight Club practically opens with the line "When you have insomnia, you're never really asleep." The Narrator tells the audience right up front that all they're about to see hovers somewhere between reality and dream.

This line is probably the most direct vocalized bit of foreshadowing in regards to the third-act twist. Tyler Durden enters The Narrator's life to change him irrevocably because he's tired of sleepwalking through something that should be enjoyed.  "This is your life, and it's ending one moment at a time."

NEXT: Fight Club & 9 Other Reasons Why 1999 Was The Greatest Year In Film