Batman has been in the crime-fighting game for almost 80 years now, and yet so much of his life, his origin, his villains and even his butler are still shrouded in mystery. As one of the most popular comic book characters in the world, it's no surprise that fans have tried to justify little inconsistencies with their own theories, or draw conclusions just to make things a little more interesting for themselves. Hundreds of comics, movies, TV shows, books and video games have been spawned from the Batman franchise, and sometimes even the weirdest versions of Batman's story seem to support these odd theories, or even suggest new ones of their own.

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What really happened to Bruce Wayne's parents in that alleyway? Where does the Joker come from and why is he so obsessed with the Bat? What makes Alfred so dedicated to Bruce, to the point of basically being a surrogate father figure? Some fans think they've figured out the answers to these questions and more, and if not, they're at least fun to think about. Are these fans as crazy as the Joker or are the answers hiding in plain sight? Here are 15 Batman fan theories that will freak you out!

15 BATMAN MURDERED THE JOKER

Batman Kills Joker

Batman famously only has one rule that he refuses to break: he does not kill. One popular theory suggests that in Alan Moore's The Killing Joke, after the Joker had tortured and possibly killed Barbara Gordon and pushed Batman to the end of his limits, Batman breaks his rule. DC later worked The Killing Joke into its continuity, but it was originally intended as a standalone story.

The final panels show Batman starting to laugh hysterically at the Joker's final joke. One panel shows Batman's hands resting near the Joker's throat, and in the final two panels, the laughter ceases, as if cut off. The animated version of The Killing Joke pushes it one step further. With the two men laughing, Batman slowly rests his hands just below the Joker's throat, and as the camera pans down, the Joker suddenly goes silent as Batman continues to laugh maniacally.

14 THE JOKER KNOWS HE'S IN A COMIC BOOK

Joker-Knows-Comic

The Joker's one prevailing character trait throughout every portrayal of him is that he's completely insane. Fans have tried for decades to come up with methods to his madness, but one particularly interesting theory suggests that it's not madness at all. The Joker is actually afflicted with "super-sanity."

This affliction is actually mentioned by name in Grant Morrison's Arkham AsylumHe sees everything in the world as it truly is and understands the ridiculousness of a world that worships a man dressed as a bat who wears his underwear on the outside, a world with Penguin-themed criminals and a Calendar Man. He realizes this kind of logic could only exist in a comic book, which is why he appears so sadistic. His violence only entertains the readers. This explains why he's spoken directly to the reader on occasion with lines like, "You're not gonna wanna miss this."

13 ROBIN IS A FAILSAFE WEAPON AGAINST BATMAN

Robin-Weapon

On one hand, it doesn't make much sense for Batman to constantly endanger the life of a child by bringing him along for fights against sadistic killers and mutant beasts. For a superhero, one would even say it's pretty irresponsible, but what if there's another reason Batman trains Robin?

It's well known that Batman has a contingency protocol of weaknesses against every member of the Justice League in case they should one day turn to evil, but what if Batman himself is compromised? Who knows more about Batman than Robin? Who knows all his combat techniques, all his gadgets, all his secrets, all his weaknesses? As the only person trained under the Dark Knight, Robin is the only person who could take Batman out if he ever went dark.

12 BATMAN IS ACTUALLY THE VILLAIN

batman-is-the-villain

Bruce Wayne is basically rich beyond spending capacity. With all that money, shouldn't he be able to clean up crime just by investing in law enforcement training, prison security and Gotham's infrastructure? Batman is constantly beating up thugs who have to take jobs as petty crooks just to get by in Gotham, but Bruce has enough money to make every citizen in the city rich.

However, Bruce has an obsession. He needs to beat people up. He needs to leave the supervillains alive, so they can escape the non-secure prisons, so he can beat them up again. Batman is a master strategist, and he knows that his methods keep crime rampant, so he never has to give up being Batman. Even Batman: The Animated Series understood this, asking in the season two episode, "Trial," "Did the criminals of Gotham create Batman or did he create them?"

11 ALFRED IS BRUCE'S REAL FATHER

Alfred-Father

There are dozens of variations on this theory, and it's a fairly easy one to understand. After all, Alfred basically serves as a surrogate father in every incarnation of Batman, dispensing fatherly wisdom, guiding him toward doing the right thing, letting him dress up like a bat to fight crime. Standard dad stuff really.

It makes sense that Alfred would help young Bruce through a troubling time after his parents were murdered, but why would he stay so devoted to Bruce well into his adult years? The theory goes that Alfred and Martha Wayne had an affair, and after the Waynes were murdered, Alfred stayed on to raise his son, but never revealed his true parentage, so as to not soil Bruce's image of his mother, the one woman Alfred loved.

10 THE DCEU'S JOKER USED TO BE ROBIN

Joker-is-Robin

It was established in Batman v Superman: Dawn of Justice that Robin has already come and gone by the time we get to the film's story. Nobody mentions him, but Bruce walks by a Robin suit with the words "HAHAHA! Joke's on you BATMAN" spray-painted on the front. The obvious first thought is that The Joker killed Robin, but there might be more to it.

Eagle-eyed viewers have pointed out that Jared Leto's Joker appears to have faint scars on his shoulders exactly where the Robin suit has bullet holes. He also has a tattoo of a Robin with an arrow through it on his arm, which seems like an odd addition when every other tattoo is dedicated to himself. The official word on the matter is that this theory is false, but if fans figured out your master plan after two movies, what else would you say?

9 HE OWNS ALL OF GOTHAM'S VENTILATION COMPANIES

batman-HVAC

It's a well-known trait of Batman's to spend a lot of time crawling around heating vents and air ducts to stealthily make his way through factories or drop in on villains. This is especially prevalent in the Batman: Arkham series of games where you spend all most as much time crawling around vents as you do punching people in the face, but Bruce Wayne is around 6'4" (including bat ears) and probably upwards of 210 pounds. Air ducts this size would realistically be terribly inefficient for heating and air conditioning.

What possible reason could Gotham have for making their air ducts so huge? Simple: Bruce Wayne, being the master strategist that he is, plans ahead to use the heating, ventilation and air conditioning (HVAC) systems as a tactical advantage and bought up all the companies in Gotham so he could give his own "Batman-sized" parameters for their construction.

8 BRUCE WAYNE DIED AT THE END OF THE DARK KNIGHT RISES

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On the surface, it looks like Bruce Wayne lived at the end of The Dark Knight RisesAfter all, we see him sitting in the restaurant in Florence that Alfred goes to at the end of the movie. Earlier in the movie, Alfred said that every year on his trip to Florence, he imagines seeing Bruce sitting across from him in a restaurant. Is this just his imagination too?

Alfred's reaction is pretty calm for seeing that his lifelong surrogate son is still alive. He just nods and leaves. Also, how would Bruce know what restaurant to go to in Florence, at what time and where to sit to be opposite Alfred when he gets there? Speaking of impossible, we see him piloting the Batplane five seconds before the city-destroying bomb explodes. Even if he ejected from the plane, there's no way he could have cleared the blast radius.

7 THE JOKER IS BATMAN'S BROTHER

Joker-Brother

The Joker is obsessed with Batman in every form of media we've ever seen him in. There are other heroes in the DC universe, and Batman isn't even the only non-superpowered one. What is it about Batman that keeps the Joker so enthralled with him? What if they're quite literally drawn together, intertwined... by blood?

The theory is that Bruce had an older brother, Thomas Wayne Jr., who sustained a brain injury that caused him to go insane. The Waynes committed Thomas Jr. to Arkham Asylum until one day he would escape and become the Joker. The idea of a long-lost brother has popped up over and over again in the Batman comics, and the concept of The Joker and Batman being two sides of the same coin is a theme of nearly every movie, comic, game or cartoon featuring both characters, from Batman: Arkham City to Tim Burton's Batman.

6 GOTHAM LEGALIZED GAMBLING

gambling-gotham

One of the biggest questions regarding Joel Schumacher's Batman films after "Why do these exist?" is "Why is everything so different?" These movies are supposed to be take place in the same continuity as Tim Burton's Batman films, but everything is different. In Batman ReturnsGotham City is a dark, gritty and somber, but in Batman Forever, it's all neon lights, flashy statues and tacky decor.

Why? Because Gotham legalized gambling, leading to prosperous times for the citizens and an image overhaul. It even turned somber Batman into a mascot, a tourist attraction. While there's one gambling scene in Batman Returns, it's at a charity event and therefore legal. Batman Forever has people gambling out in the open, even featuring a casino robbery scene as if to underline this change.

5 ALFRED HIRED JOE CHILL TO KILL THE WAYNES

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This one actually ties into the "Alfred is Bruce's father" theory. Alfred and Martha have an affair, and Alfred falls in love. He wants to raise Bruce with Martha, but of course she would never leave a billionaire CEO for a butler. In a fit of rage, Alfred hires Joe Chill to kill Thomas Wayne so that he and Martha can be free to be together and raise Bruce as their son, but during the job, something goes terribly wrong.

When Joe attempts to shoot Thomas, there's a struggle and Martha is shot first. He finishes the job and runs off. Alfred, grief-stricken and wracked with guilt over his actions, raises Bruce as a Wayne, and never lets on that he is Bruce's real father, knowing that Thomas was the far better man, and Bruce deserves an honorable father.

4 THE JOKER IS THE HERO IN THE DARK KNIGHT

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Throughout The Dark Knight, we're led to believe that The Joker is an agent of chaos, causing havoc and mayhem wherever he goes, so why does every action he take actually make Gotham a better place? Before he showed up, Gotham was a crime-riddled mess, but Joker shows up and within a short period of time, almost all organized crime was eliminated, many corrupt officials were jailed or killed and the city's violent vigilante went into hiding for eight years.

The mafia bank robbery at the beginning lures Lau out of hiding with all the crime families' money. When he threatens to blow up a hospital, it outs corrupt police officials who Harvey Dent later kills. He's responsible for Gordon, one of the few incorruptible men on the force, being promoted and Batman serves as an example that vigilante justice cannot stand in civilized society. The Joke was on us all along.

3 THE JOKER IS AN IMMORTAL METAHUMAN

An image of the Joker peering out of the shadows in DC Comics

The Joker has been shot, drowned, strangled, stabbed, beaten, electrocuted and dropped from incredible heights, yet he not only always survives, but he always comes back just as limber and energetic as ever. One theory as to why suggests that in the same accident that bleached his skin and drove him insane, his metahuman gene was triggered and he became effectively immortal.

How else can you explain that he would survive falling into a vat of acid in the first place without blinding him or severely impairing him in any way? Batman: Endgame by writer Scott Snyder and illustrator Greg Capullo actually suggested something similar in that the Joker heals himself in a dionysium pit to regenerate his wounds, but that's likely just to heal physical ailments (like having his face cut off), while still being immortal.

2 BATMAN'S LIFE IS ALL AN ELABORATE HOAX

batman-hoax

As we learn in Batman Begins and Batman: Year One, Bruce leaves Gotham for several years before returning to run his father's company, but at first he had no interest in being a CEO. Bruce just wanted to fight crime. The theory suggests that Wayne Enterprises was near the point of bankruptcy until Bruce returned, and with the help of Alfred, the WayneCorp board schemed a way to bring him back into the company.

They hire costumed actors to act as criminals for Bruce to take down. This explains why the police force has a bat-signal to enlist a costumed vigilante (how better to bring him into controlled situations?), why Batman never loses even against insurmountable odds, why almost no one ever dies and why Gotham hasn't executed the Joker, even after years of homicidal terrorism.

1 BATMAN IS A PATIENT IN ARKHAM ASYLUM

batman-asylum

No one is denying that Bruce Wayne is kind of crazy. He dresses up as a bat and jumps from skyscrapers to fight crime after all, but what if that's all just in his head? The theory goes that after Bruce's parents were murdered, he suffered a mental breakdown and was locked up in Arkham Asylum.

Each of his villains represents either one of the employees at Arkham or an aspect of his fractured psyche. Among other things, it would explain why after he started dressing up as a bat, every criminal in the city seemed to want to theme their crimes with riddles, jokes, calendars or ice puns. It also explains why no one suspects that the hero who can afford batmobiles, bat-copters and endless gadgets is secretly the only guy in the city who could afford all that.

You've got to let us know in the comments what other insane fan theories you've heard about the Dark Knight!