The third story, BATMAN: SHADOWS, featured the introduction of Dr. Hugo Strange of Arkham Asylum and the birth of Two-Face, as well as the appearance of several other major Arkham denizens. Also brought Rene Montoya into the mythology, as Bullock had been there since BATMAN: GENESIS. The whole "Do I cause the madness in Gotham" angle and "Can I keep doing this without losing my own mind" was the major theme here.
Gotham was debating the value of Batman's presence given the attraction of men like The Joker. The story began with the pursuit and capture of serial killer The Scarecrow. The Scarecrow was the latest in a series of "Arkham" threats to Gotham. Bruce Wayne was making headway in Gotham, with The Wayne Foundation going full steam. Newcomer/opportunist Oswald Cobblepot was making things difficult for him on both the business and the mob side of things, but Batman was keeping him in check, using him for information more than anything else. So was Dent. The political corruption had been mostly cleared out with the arrival of a new Mayor: Krol (Hamilton Hill was in the second story). Gordon became Commissioner and had formed a new Major Crimes unit.
The beginning of the story dealt with the stress Bruce Wayne was undergoing trying to keep Gotham clean with emerging mob/gang elements in the vaccum left by Falcone's organization (This was The Penguin's influence). Harvey Dent began the prosecution of Falcone toward the beginning of the story (He tried to do so in GENESIS too, and failed miserably due to corruption, so this was like a "full circle/second chance" kind of thing.
There were copycat Batman dealing out violence to Gotham criminals, and this became an issue. Batman went hunting for them, ran into Catwoman. Bruce and Selina were a quasi item again, with Catwoman mixing things up for Batman now and then. There was a staged riot at Arkham Asylum toward the middle of the story, presumably started by The Joker, with all hell breaking loose and Batman arriving. Strange was behind this, apparently meaning to gauge the Batman's skill and observe his methods. Strange was taken hostage by The Joker/Zsasz in different versions, and rescued by Batman.
Harvey Dent, who had started to have shady dealings with Maroni in the prior storyline, now started having them with The Penguin, who essentially sold him to Falcone. Having used up his goodwill with the mob, he was scarred for being two-faced with them during a court appearance, and later, when Falcone's case fell through a second time, went on his personal vendetta against those the law would not prosecute or punish outright. He turned against his former friend James Gordon, too at one point, only sparing his life because of the coin toss, which Montoya convinced him to do.
At roughly the same time, Bruce Wayne, who had been hunting for the imposter Batman, was lured into a trap by Hugo Strange, who sought to replace him (the source of the copycat Batman), believing that Batman wasn't doing enough to stem the violence in Gotham. It was a pseudo KNIGHTFALL/STRANGE APPARATIONS kind of thing, except that Strange actually became Batman and went out and did things, he didn't just talk about it. Strange, who had contacts with The Joker, also served as a sort of twisted mentor/shrink to a spiraling Harvey Dent/Two-Face and to Bruce Wayne after he was captured. He and Dent shared the same ideas about justice. The idea was that Strange realized that you could not rehabiliate the kind of evil that infested Gotham. That it had to be eradicated. He imprisoned Bruce Wayne in Arkham and kept him on a diet of fear toxin, leading to all kinds of fun hallucinations.
Catwoman investigated the disappearance of Bruce Wayne and Batman, she and Gordon crossed paths, and eventually joined forces along with Gordon, Sarah Essen, Bullock and Montoya to help Batman when Catwoman tracked the imposter back to Arkham. Two-Face was wreaking havoc throughout all this, killing city officials and political people (judge), forcing Gordon to prioritize.
Bruce Wayne escaped Arkham and stopped Hugo Strange. He then had to go back to Arkham, where the inmates, specifically Two-Face and The Joker, had taken over. In his weakened state he was pretty much no match for the inmates, though he made a hell of an effort. There was a "Trial of Batman" sort of scene at the end, with The Joker, Dent, and the inmates of Arkham overseeing The Dark Knight's fate.
In one version of the script, Dick Grayson was introduced when Bruce and Selina went to a Cirque De Solei type performance, and though he aided Batman in the end during his "trial", he did not become Robin. I wrote him out, as it was just too forced. If Strange was in, Dick could not be, and I really liked having Hugo Strange play a role.
The Joker took part in the trial of Batman as well as serving as an informant of sorts, and ended up murdering Strange for daring to try to usurp and kill Batman.
Quite honestly, the script was a mess when I lost it, although it had some great elements and nods to the mythology. I kept putting Strange in and then taking him back out. At one point I removed him and wrote a 45 minute fanfilm based on his elements, which I'm still looking to film at some point. But I'd only written about 70 pages of it, and it would have been at least 130, and I was confident that I could get it to work. There was a lot going on, but it all c ould have come together fairly well. Basically everything culminated in Arkham, and that's where it was going to end. I couldn't think of where to go for a fourth storyline other than maybe Robin. I kicked around a Batman, Robin, Ra's Al Ghul and Talia storyline, but I'd already done that one with THE DARK KNIGHT.