Travis Bickle (Robert De Niro) is a man with a plan. He’s going to kill Senator Charles Palantine (Leonard Harris). “My whole life is pointed in one direction,” Travis writes in his diary. “There has never been a choice for me.” However when the mohawked murderer shows up at Palantine’s campaign rally, he’s spotted by Secret Service agents and loses his nerve.

Bickle escapes into the crowd, but while he’s failed his mission, the taxi driver is still boiling with rage—against the Senator, against his ex-girlfriend Betsy (Cybil Shepherd), against New York and the “scum” of the world. And that’s when “Operation: Kill Palantine” becomes “Operation: Save Iris.”

In the film’s bloody climax, Bickle attacks a brothel, killing Sport (Harvey Keitel), a bouncer, and an angry gangster, thus “rescuing” Iris (Jodie Foster) from a life of prostitution. When armed police officers storm the room, they find Travis covered in blood, miming a pistol with his hand and committing mock suicide.

Up until this point in the film, everything has been pretty straight forward. Travis is a crazy person who wants revenge against everyone and everything. When he can’t shoot his ex-girlfriend’s boss, he goes after Iris’s pimp, killing three people in the process. And that’s when things get a little ambiguous.

After the shoot-out, Martin Scorsese gives us an overhead shot of the brothel. (Scorsese calls this the “priest’s eye view” because it’s similar to how a priest looks down at an altar.) As the camera slowly pans down the hallway and into the street, we see the blood-stained walls, the bodies slumped on the floor, and the curious spectators gathered outside. The scene then cuts to Travis’s apartment where the walls are now covered with newspaper clippings celebrating Travis as a hero for killing a Mafia boss.

Stranger still, as the camera pans across the wall, we hear the voice of Iris’s father, thanking the taxi driver for saving his daughter. After the monologue, we watch as Travis picks up Betsy in his cab and drive her home. During their short commute, Betsy almost expresses remorse for rejecting Travis. When she steps out of the cab, Bickle refuses to let her pay for the ride and drives off into the night, leaving Betsy behind.

What just happened?

Well, some people believe the last few minutes of Taxi Driver (1976) are actually an extended dream sequence. The theory goes that Travis was fatally wounded in his shoot-out, and as he bleeds to death, he imagines a world where he’s celebrated for his actions. In Travis’s fantasy, the newspapers laud him as a crusader, Iris goes home to her parents, and Betsy sees the error of her ways and comes back for a second chance.

Admittedly, there are some odd details that might indicate the ending is Travis’s death dream. Iris never indicated a desire to return to her old life, and when Betsy dropped Travis, it seemed pretty clear she didn’t want anything more to do with the creepy cab driver. It all seems a little too perfect that Travis suddenly went from psycho loser to white knight, especially since his claim to fame is murdering three people. Some even say that overhead shot symbolizes Travis’s soul leaving his body and floating above his blood-soaked masterpiece.

Film critic Roger Ebert gives credence to this interpretation in his “Great Movie” review. Published in 2004, Ebert wrote, “Is this a fantasy sequence? Did Travis survive the shoot-out? Are we experiencing his dying thoughts? Can the sequence be accepted as literally true? I am not sure there can be an answer to these questions. The end sequence plays like music, not drama: It completes the story on an emotional, not a literal, level.”

Of course, not everyone buys the “It Was All a Dream” theory. Film critic Devin Faraci argues this interpretation “profoundly misses the entire point of the ending of Taxi Driver, and it fundamentally denies the movie its complete message.” According to Faraci, Bickle most definitely survives the gunfight, and he isn’t the only who says Travis made it out alive.

In an interview with The Guardian, De Niro mentioned how he wanted to make a sequel to Taxi Driver, indicating his belief that Travis is very much alive. And in a Reddit AMA, screenwriter Paul Schrader explained, “The epilogue is not a dream sequence….” So if Travis really survived, then what is Taxi Driver trying to say?

Well, in Paul Schrader’s commentary track for the Collector’s Edition of Taxi Driver, he mentions how Sara Jane Moore—the second woman who tried to assassinate President Gerald Ford—ended up on the cover of Newsweek. Schrader was baffled by the magazine’s move. After all, this woman had tried to kill someone, and now she was on the cover of a magazine, like some sort of celebrity. Inspired, Schrader wrote an ending where America turns a psychotic gunman into a national hero. Travis becomes an idol to the very city he despises, the same place he wants the rains to wipe away. That doesn’t say a lot for America’s values.

It’s quite similar to the ending of The King of Comedy (1982) in which Rupert Pupkin (Robert De Niro, once again) takes a talk show host (Jerry Lewis) hostage and then replaces him on TV. Even though Pupkin is clearly disturbed, he becomes a late night sensation and a bestselling author. He becomes a celebrity, even though he’s a crazy kidnapper. Bickle and Pupkin are essentially the same character (though Travis is far more violent), and both movies have the same message. America really loves its bad guys.

Well, that’s the message so long as you think Travis survives. If you believe Bickle dies, suddenly the meaning of the entire movie changes. It stops commenting on society and instead simply becomes a disturbing portrait of a truly troubled mind (not that that’s a bad thing). However, if you side with Scorsese and De Niro, then it’s a film taking aim at America as a whole, a civilization that glorifies psychos, vigilantes, and villains.

But what does Martin Scorsese have to say about the ending? Well, according to the director, Travis survived the shoot-out…and chances are good he’s going to erupt again. In the last seconds of the film, Travis looks into his rearview mirror and sees his own wild eyes looking back. We get one last glimpse of his insanity, churning under the surface, and there’s suddenly a harsh, strange note on the soundtrack as Travis adjusts his mirror and looks away from his reflection. According to Scorsese, “I decided I’d put something on that shows that the timer in Travis starts to tick again, the bomb that’s about to explode again.”