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Now a documentary is being planned to shed light on what the film would have been like.

Tentatively titled Miller’s Justice League Mortal, the documentary comes from Australian director Ryan Unicomb and producers Aaron Cater and Steven Caldwell, who announced the project via Inside Film. They have investors on board and may turn to crowdfunding as well, which would make it follow in the footsteps of The Death of Superman Lives, the documentary about Tim Burton's aborted Superman movie.

“We wanted to get the story out there to help us to gauge interest,” Unicomb told the site. “I have always been fascinated with project, which would be in the same vein as 2013’s Jodorowsky’s Dune and this year’s The Death of Superman Lives: What Happened?"

Justice League Mortal was developed around the same time as Christopher Nolan's Batman films, with the director reportedly not keen on two versions of the Dark Knight existing on film at the same time. The writers strike of 2007-08, as well as a rumored-to-be-rising budget, didn't help matters either.

The film also had cast Common (Green Lantern), Santiago Cabrera (Aquaman), Teresa Palmer (Talia Al Ghul), Zoe Kazan (Iris Allen), Hugh Keays-Byrne (Martian Manhunter) and Jay Baruchel (Maxwell Lord).

In 2014, stuntman Greg Van Borssum posted a photo with Miller and most of the cast together in 2007:

The documentary team didn't give a timeline for when their film might be completed.

While this version of Justice League never hit the big screen, Warner Bros. has Justice League Part 1 slated to hit theaters in 2017, with Part 2 coming in 2019. Zack Snyder is directing both.

The doc would be the latest in a string of looks at films that were never made, joining this summer's Death of Superman Lives, 2013's Jodorowsky's Dune and the upcoming Doomed: The Untold Story of Roger Corman's Fantastic Four.