If snippets and summaries from what's purported to be a copy of George Miller's Justice League: Mortal script are to be believed, the film would have included quite a bit of material familiar to comic book fans--including Barry Allen sacrificing himself in the midst of a Crisis, Wally West taking on the mantle of The Flash and the death of Checkmate head Maxwell Lord at the hands of a Justice Leaguer...
...albeit probably not the one you'd expect.
Comic Book Movie found the piece, which feels a bit too neat and fan fiction-like to convince us completely...but one never knows. After all, it's not as though Warners has kept a tight leash on other unproduced projects, like the Superman script done for the J.J. Abrams version of that film which never happened and which subsequently leaked into the wild.
Maxwell Lord and the OMACs are a primary threat in this story, with Lord's story ending with a snapped neck--but this time from Batman, not Wonder Woman, as Diana looks on shocked like Superman did to her in the comic book source material. It draws heavily from JLA: Tower of Babel and the Infinite Crisis tie-in Superman: Sacrifice, which is where they dealt with Max Lord mind-controlling Superman.
Of course, with Wonder Woman playing a major role in the film, that's a point on anything going on at Warner Bros. right now, where she seems to be in a holding pattern. The newest iteration of the Justice League movie, which seems to be in a holding pattern, will almost certainly feature the Amazing Amazon, but as a result, her planned TV series is reportedly on ice.
Check out way more details on the project here--assuming, of course, that any of this is true.