When it comes to inspiration, the most recent Batman films have taken a lot from comic book writer/artist Frank Miller. Christopher Nolan’s Batman Begins owes a lot of its characters, tone, and structure to Miller’s seminal Batman: Year One, and the entire visual design of Batman in Batman v Superman: Dawn of Justice is directly influenced by the iconic imagery in Miller’s game-changing The Dark Knight Returns. It’s fair to say that an entire generation of moviegoers have been ingesting Miller’s particular brand of Batman without even knowing it.

This ends up being something of a shock when it turns out that Frank Miller actually wrote his own Batman film. After the disastrous response to 1997’s ultra-camp Batman & Robin, Warner Bros. decided that the next Batman film had to stray as far away from that tone as possible. They enlisted Miller’s services in order to craft a story that returned the “dark” back into the Dark Knight. Not only would Warner Bros. hire one of the most important figures in Batman’s literary history, but they also attached a filmmaker, Darren Aronofsky, who was just coming off a run of incredibly gritty features in π (Pi) and Requiem for a Dream (and who would later direct such fantastic films as The Wrestler and Black Swan). Aronofsky is an avowed fan of comic books and genre fiction, once being attached to such prestigious fan projects like Wolverine and RoboCop. The opportunity to work with Frank Miller on a brand new cinematic vision of the Caped Crusader was too enticing to ignore.

And what a vision it was. Though Miller did draw inspiration from his own Batman: Year One comic series (the script’s title is even called Batman: Year One), Miller and Aronofsky wanted to reinvent the character of Batman in a bold way. In their proposed film, Bruce Wayne is not a playboy billionaire. In fact, he’s not even a millionaire. In Batman: Year One, Bruce Wayne has no wealth to his name at all. After the death of his parents, he grows up on the streets of Gotham City, learning all he can about martial arts and detective work through various books he manages to get his hands on. He’s eventually taken in by the owner of an auto garage. The owner’s name? Little Al.

Yes, this version recast Batman’s trusty butler Alfred as a middle-aged black man who makes a living repairing cars — and one of those cars is a Lincoln Continental that eventually became the Batmobile. Are you starting to get how radically different Aronofsky and Miller’s take on Batman would have been? It doesn’t stop there. In this version, Bruce is very clearly suffering from mental problems, often taking medication for his psychological issues. This was the truly damaged and unfixable version of the character that makes a lot of sense for a more brutal, darker spin on the Batman mythos.

And the darkness keeps coming in Miller’s script (though I’m sure Aronofsky worked on it as well): Catwoman is introduced as an S&M dominatrix (she’s also African-American in this version, much like she was in Miller’s Year One comic), Jim Gordon is a suicidal cop who has been living in Gotham for years and wants to get out, and there is noir-styled voiceover that was directly inspired by the inner monologuing of Travis Bickle in Taxi Driver. Miller and Aronofsky were determined to make an R-rated, adult-focused Batman story that didn’t shy away from the more disturbing elements of the character that other films hadn’t really explored. At the time, Warner Bros. was entertaining the idea of making multiple Batman films that would target different age demographics, and Batman: Year One would have been its adult venture.

Although some concept art (seen above) was produced for the movie, the movie never made its way into production. It’s believed that Warner Bros. lost faith in the project and decided to use it as a stepping stone towards a more grounded take on the character. That eventually led to Christopher Nolan’s Batman Begins (interestingly, Aronofsky was pursuing Christian Bale for the lead in Batman: Year One) and the “Dark Knight trilogy” we have today.

While there are some aspects of Batman: Year One that fly a little off the deep end, the basic concept of a Batman without a bank account is too good to pass up. Many people criticize the character for his inordinate amount of money— especially as it refers to his treatment of lower class citizens — but what has always been the strongest foundation of the character isn’t his cash; Batman is the most driven (to the point of psychosis) of any superhero, and Batman: Year One illustrates that cursed motivation extremely well.

I also like that Batman: Year One doesn’t shy away from a fact that a lot of Batman fans would like to ignore: Batman is certifiably insane. With the exception of the Punisher, Batman is easily the most deranged of the mainstream superheroes. It’s easy to write a lot of this off when he has an inexhaustible amount of money (rich people aren’t crazy, they’re eccentric), but when Batman: Year One takes that away from him, the obviousness of Bruce’s mental instability and terrifying resolve come to the forefront in alarming ways. That makes the character and his actions much more difficult and therefore much more interesting.

By no means a perfect script (that voiceover is really bad), Batman: Year One is still the greatest Batman movie never made because it’s the riskiest idea that’s ever been in serious contention for a shot at the silver screen. One of the reasons characters like Batman have remained prominent in pop culture is because they allow themselves to be manipulated and toyed with in an infinite number of ways. Batman: Year One wanted to mess with one of the fundamental elements of Batman (his wealth) and see where that took the character. Darren Aronofsky said it best when he was asked about what drew him and Frank Miller to the project: “We tried to ask that eternal question: ‘What does it take for a real man to put on tights and fight crime?’”

Aronofsky and Miller’s answer to that question? A movie we’ll never get to see.