Black Swan director Darren Aronofsky and Frank Miller worked on a Batman film project that never left the cutting room floor, and the Dark Knight comics writer has now shed light on why.

In an interview with The Hollywood Reporter, Miller said Aronofsky's "vision of Batman was darker than" his own, and ultimately not kid friendly enough for Warner Bros. to greenlight. In fact, the director planned to have the iconic DC superhero torture his foes.

"My Batman was too nice for him," Miller explained. "We would argue about it, and I'd say, 'Batman wouldn't do that, he wouldn't torture anybody,' and so on," he added, noting that while they "hashed out a screenplay" and were handsomely paid for their work, the studio wasn't on board with Aronofsky's vision. "The executive wanted to do a Batman he could take his kids to. And this wasn't that."

The film wouldn't have lent itself to merchandising either, as the "Batmobile was just a tricked-out car" and his iconic lair was constructed in an abandoned subway. In fact, Aronofsky wanted to create a Batman who "turned his back on his fortune to live a street life so he could know what people were going through."

While Aronofsky's vision for the iconic superhero won't be hitting the big screen anytime soon, Zack Snyder's cinematic take on the Dark Knight will make his grand debut later this month, when Batman v Superman: Dawn of Justice opens on March 25.