Okay, here we go...
The problem with Arkham City is that there are too many terrific ideas in the proverbial basket. The creative team would have to select one of two storylines if they wanted to make a critically and financially successful film. In scenario one, they focus on Joker dying and electing to go out with a bang, or they focus on Strange creating a super-large and lethal ghetto in the heart of Arkham City. Each of these plotlines would sustain a 2.5 hour film beautifully, but together cannot be applied to a single film, unless they go for Peter Jackson lengths, which is not advised, as fans and critics have expressed their displeasure with Jackson's penchance for three hour dramas. (Note: a miniseries would resolve this problem in a heartbeat. Go for the True Detective length and episode number.) If one elected the Strange route, they would have to omit the Joker, and replace him with another villain who is as unique, but not too iconic as to draw attention away from Strange. Since it isy the Sionis Steel Mill, it would be easy to select Black Mask and say that Tyger was unable to apprehend Joker, which would feed into the mystique of the New 52 Joker (think about how he was gone for a year and no one, not even the World's Greatest Detective, had an idea where he was.)
With that in mind, model the film on Escape From New York, and really illustrate the growing gang warfare (which was not fleshed out as much as it should have been in Arkham City. Sure, there was ornamentation on the buildings that marked the boundaries of each criminal, but all of the violence between said factions was offscreen, relayed through the local surveillance or Oracle's observations.) Still, there would have to be some pruning done with AC"s master narrative, so I'd excise the Freeze subplot, R'as, as well as the side missionms.I'd focus on the gangwar between Two-Face, Penguin, and Black Mask, as well as Protocol Ten. It would be a tightly wound 2.5 hour thriller focusing on the inevitable destruction of Arkham City, whether it be from the gang war or Protocol 10.
Or, with the Joker plot in mind, have the beginning focus with Joker and Harley and crew taking over the Sionis Steel Mill and preparing for his final bout of glory, as he is dying. Retain the poison subplot, Freeze subplot, as well as the R'as business; it would be fascinating, from the narrative and visual standpoint, to meditate on the end result of the resurrection imagery juxtaposed atop the imagery of death (Joker and his Jokerized Steel Mill.) To minimize police intereference, use the plotline from AA, with Joker claiming he installed bombs all over Gotham. Have Batman operating in a limited timeframe before a full scale assault of his section of the city occurs, and overlay that on the limited timeframe of Batman trying to find the cure for the toxic blood within his system. Plus, build up on the irony of Joker-poisoned blood being used to save lives in cutaways, to emphasize the dire nature of the situation. End the film as AC did, with the Cain allusions.
Thus, I have outlined the two possible routes for AC. As a game, the narrative shortcomings are compensated by the gameplay; however, converting the game narrative to a film narrative requires compacting and excision.
