When Fight Club first hit theaters back in 1999, it received a lot of attention for its genuinely shocking plot twist. Nobody expected Tyler and the Narrator to be the same person, yet maybe they should have, because there are tons of Easter eggs in Fight Club.
Director David Fincher crammed Fight Club secrets and genius foreshadowing into every available frame. Most go by so quickly it's almost impossible for first-time audiences to notice, but there are definitely a few in there that everyone should have picked up on.
After knowing the twist, it becomes much easier to notice the little things that give it away: shared boxers, impossible phone calls, shifting car seats. Even after multiple viewings, there may still be some brilliant instances of foreshadowing you missed.
After the Narrator's apartment blows up, he needs somewhere to stay. He calls the number Tyler Durden gave him, but there's no answer. Within a few seconds, Tyler calls the Narrator back on the same payphone.
However, if you look a little closer, there's an inscription that says the phone doesn't do incoming calls. This means it's impossible for Tyler to call back - if he was a real person, anyway.
Before the Narrator has even met Tyler Durden, Tyler starts showing up in hallucinations. The Narrator is suffering from insomnia, so strange flashes and visions aren't entirely ridiculous, but it's unsettling to think he's seeing glimpses of a man he's never met.
That means he already knows who and what Tyler is before ever "meeting" him.
Tyler makes a brief appearance at the support group the Narrator attends. Again, this is pretty disturbing since the Narrator doesn't know Tyler yet.
Tyler and the Narrator get into a big argument mid-way through the film that results in a serious car crash. The car tumbles several times, but when the Narrator is removed from the vehicle, he's clearly dragged from the driver's seat of the car.
This is pretty weird, since the Narrator was previously shown in the passenger's seat as Tyler drove. It's almost like they're the same person or something.