Bruce Wayne has worked hard to keep his identity as Batman a closely guarded secret from everyone (except his butler Alfred, Superman, Wonder Woman, Batgirl, Ace The Bat Hound, at least half a dozen Robins, the Outsiders, and the entire Justice League). Thanks to his brilliant acting ability and mastery of disguise, few people would suspect that billionaire playboy philanthropist Bruce Wayne is secretly the Caped Crusader. At least… in his universe.

In the Marvel Universe, however, this is a different story as multiple characters have shown they have a very easy way of uncovering the Dark Knight’s secret identity. And all it takes… is the purchase of a single movie ticket.

Related: Spider-Man Once Thought He Was BATMAN (Yes, Really)

During the 1990s, when movies like Tim Burton’s Batman and Batman Returns were taking the world by storm, even the Marvel Universe ended up getting into “Bat-Mania.” In one issue of The Fantastic Four, for instance, Ben Grimm and his girlfriend decided to go see Batman. While the Thing did enjoy the movie, he found the idea of some "bozo" dressing in long johns and hanging out in a mansion with Kim Bassinger was just too unrealistic.

Other Marvel heroes also got into the fun. While stopping some terrorists on the Statue of Liberty, Spider-Man grabbed one of them menacingly and pulled him close to his masked face. When the horrified man gasped, “What are you?” Spidey answered, “I’m Bat – ahem – I’m Spider-Man!”

A few years later, after Burton’s Batman sequel was released, Spidey had to fight a whole team of armored thugs. While facing off against one of them, Spider-Man fired a web line but ended up hitting the wall behind the thug and not his opponent. When the thug mocked Spidey for missing, Spider-Man calmly suggested that the thug should see a movie and recommended Batman Returns before using the web line to rip the entire wall off and send it smashing against the thug.

Related: Michael Keaton’s BATMAN Got A Sequel Fans Weren’t Allowed To See

Obviously, these examples of meta humor were intended as jokes and playful winks at the reader. However, when Marvel and DC began having regular crossovers, allowing characters like Spider-Man and Daredevil to meet up with Batman, one wonders why none of them brought up the fact that Batman’s secret identity is public knowledge in their universe. Granted, some of these heroes (particularly Daredevil) might not go to the movies often. Another explanation is that the characters’ memories are altered during crossovers to prevent any major changes to the universe. Or there’s another explanation…

During the meta-action/comedy movie The Last Action Hero, a boy got sucked into an action film starring Arnold Schwarzenegger. He ended up getting partnered with Schwarzenegger’s character and tried to show him that he was a fictional character played by an actor. To prove this, he goes to a video store to find a poster of Terminator 2: Judgement Day, only to find that in this universe, the Terminator is played by Sylvester Stallone.

Thus, it’s not impossible to believe that in the Marvel Universe, Batman is a fictional character – but has a different secret identity (albeit one that’s still a billionaire playboy). The Dark Knight might not be able to keep moviemakers from adapting his life story… but he doesn’t have to share everything either.

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