Well before Zack Snyder gave the Batman v Superman storyline a run (with less than ideal results) DC was already planning to match up the two, with Colin Farrell as the Dark Knight and Jude Law as the Man of Steel. Perhaps you had heard this before, as details occassionally trickle out about the scrapped project.
This early 2000s idea apparently had an extremely dark storyline (even in relation to what was actually put out there) according to the man who was completing the script, Akiva Goldsman (Batman Forever, Batman & Robin). He took over the draft of the never-made Batman/Superman showdown after the original screenwriter left.
Speaking to Collider about what never was, the Hollywood veteran revealed what the plot was going to be if the film actually had been made. It was going to start off with Alfred's funeral, and then get even shittier for Bruce Wayne from there.
“I wrote on…this version of Batman v Superman [around 2001 or '02]— when Colin Farrell was cast as Batman and Jude Law was cast as Superman and Wolfgang Petersen [Air Force One, The NeverEnding Story] was directing—we were in prep and it was the darkest thing you’ve ever seen," Goldsman said. "It started with Alfred’s funeral and Bruce has fallen in love and renounced being Batman, the Joker kills his wife, and then you discover it was all a lie. Just that the love itself was constructed by the Joker to break [Bruce]."
He also talked about how the world just wasn't ready for films like that at the time. Gee, imagine a universe where DC decides to go the "super dark" route.
"It was a time where you would be able to get these sort of stories together in script form but they couldn’t quite land in the world," he added. "Somehow, the expectations of the object—whether they be audience or corporate or directorial—it wasn’t landing quite in the way I think we imagined when we put them on the page.”
Goldsman went on to compare this idea to the golden-era Batman and Superman characters that populated the panels of the World's Finest comics for a good stretch of the 20th century.
“It was really The World’s Finest, in a kind of dark and interesting way," Goldsman said. "I think it could have been lovely. On the other hand, none of me is sad that Nic Cage’s Superman didn’t get made. So, I guess in that whole period of time, there were wins to be had and losses to be avoided.”
Oh what could have been—*remembers Batman & Robin*—or maybe not. Check out the whole interview over at Collider.