The story begins with the Yellow Bastard visiting Gotham City in order to "meet the locals", accompanied by his henchmen Shlubb and Klump. His actions draw the attention of both the Scarecrow and Batman. Batman defeats Scarecrow and sends Shlubb and Klump to jail, but the Yellow Bastard escapes back to his senator father. Batman tries to interrogate Shlubb and Klump in jail, but a federal agent takes them back to Sin City before Batman can discover the identity and whereabouts of the Yellow Bastard. The news that two Mooks managed to escape Batman's grasp spreads through Arkham Asylum. The rogues gallery escape Arkham and travel to Sin City in order to set up operations under the belief that they could more easily get away with their crimes.
Of course, this doesn't sit well with Batman.
While tracking them through Sin City, Batman is faced with the corruption of the city, meeting the anti-heroes from that series as well as fighting many of its villains. Needless to say, his alliance with the likes of Marv and Miho doesn't work well.
The story weaves in and out of Sin City continuity and is narrated by various characters in each chapter. While it's not explicitly stated, the story takes place some time during the 90's era of Batman.
- Batman Gambit:
- Batman knew exactly what to pack in his utility belt in case he ran across Killer Croc or was captured by Poison Ivy.
- Big Damn Heroes: A few instances.
- Robin pops up briefly to help in the first chapter.
- Batman shows up just in time to stop Dwight from being carved up by Mister Zsasz and Mariah.
- Marv inadvertently saves Batman when he attacks Killer Croc.
- At the climax Batman is at Joker's mercy, only for Miho to step in.
- Body Horror: Joker's plan which involves setting up explosives connected to drums of a new type of toxin on the roof of an orphanage. When the bomb goes off, the children left alive (and likely horribly disfigured) would be let loose on Sin City as an army of homicidal, mutilated kids.
- Buffy Speak: How Dwight, the Yellow Bastard, and Liebowitcz describe the Techno Babble coming from Batman or the Scarecrow.
- Combat Pragmatist: In his second round with Killer Croc, Marv hits him with a car, whacks him several times with a fire extinguisher, blinds him with the extinguisher's contents, and then tries to shoot him point blank in the head. That's one way to even the score.
- Crapsack World: Sin City, as usual. The Joker describes it as a place where everyone "seems to get the joke."
- Miho seems to keep enough weapons on her to arm an entire ninja clan.
- Blue Eyes also seems to go to a lot of trouble to shove a needle in Batman's neck. Then again... it's Batman.
- Deadpan Snarker: Marv, most notably in his fight with Joker where he tries to inject him with toxin.Joker: It's just a little prick.Marv: I don't care what you got in your pants, pal!
- Diner Brawl: Wallace vs. thugs in an Italian restaurant.
- Drowning Pit: Batman gets tossed in one thanks to Poison Ivy and Blue Eyes.
- Empathic Environment: When Batman first shows up, it is during a freezing snowstorm in Sin City. By the time he leaves, it's scorching hot. There seems to be little in between, and it reflects the mood of the story.
- Enemy Mine:
- Batman has this relationship with The Riddler... for a while.
- The Sin City police force reluctantly bring Batman in on a case, knowing full well that he could expose their corruption.
- Wallace agrees to help the Magliozzi Family take down Two Face in order to protect his friends.
- Even Evil Has Standards: Scarecrow mentions that he found the Yellow Bastard "distasteful". He also seems to have little regard for his Arkham inmates.
- Fire-Forged Friends: Miho seems to consider Batman a friend after they take down the Joker. While Batman still has contempt for her, he still admires her for reasons he never fully understands.
- Genius Loci: Sin City is treated as a living being, at least metaphorically. Batman and other characters describe it laughing at them, twisting their psyche, and growling at one point.
- The Ghost: Ava Lord, the Roarkes, and Herr Wallenquist are all mentioned several times in the fic. They are major Sin City bad guys and are said to be interacting with the Batman rogues but are never depicted in-story.
- I Reject Your Reality: Despite being locked up in Arkham Asylum, the Scarecrow not only openly dismisses his fellow inmates as crazy, but refuses to believe that he is just as insane.
- Let's You and Him Fight: Averted when Batman meets both Dwight and Wallace, invoked when Batman meets Miho, and inverted when he meets Marv (they team up and THEN fight).
- No Name Given: Since every chapter is written from the POV of a different character, they don't always say the names of the people they meet:
- Batman fights Kevin, but since he's mute and Batman never learns his name, he remains nameless. Readers unfamiliar with Sin City might not know who he was.
- In the Yellow Bastard's chapter, he simply refers to Batman as "You Know Who".
- No Honor Among Thieves: Very much so. While Batman's rogues meet once in a somewhat polite manner, they make it very clear that they will turn on each other once their goals are met. Of course, the entire meeting was set up by the Riddler who planned a preemptive backstab: he had previously contacted Batman and set them up. This was so that he could get them out of the way and have full loyalty of the Sin City underworld. He is then essentially betrayed by the Sin City mob who attack Batman in such a way that they don't care if he's killed in the crossfire.
- Only a Flesh Wound: In typical Sin City/Batman fashion, the characters get beaten, stabbed, shot and more, but keep going.
- The Plan: The Riddler stages a meeting with most of Batman's Rogues and secretly sends clues to Batman to let him know about the meeting and show which rogue is the most immediate threat. He also makes a bargain not to commit any crimes until Batman captures the others. Batman knows that Riddler is doing this in order to get rid of his competition but has little choice but to follow through with the plan due to the immediacy of the situation. Riddler keeps his promise while Batman takes out his rivals but Nigma never said anything about letting the Sin City underworld know about Batman's actions or where to find him.
- Punch! Punch! Punch! Uh Oh...: When Marv first shoots/punches Killer Croc. Although Marv takes it more lightly than most cases of this trope.
- Shout-Out: A few.
- When Dwight first meets Batman, he calls him "The goddamn Batman".
- At one point, Marv drives a black 1957 Mercedes into Killer Croc. This model of car is significant in that it was one of the first Batmobile designs and is very iconic, while at the same time, vintage cars are normal in Sin City.
- Chasity, an original character, wears an S&M mask that not only resembles the bat-mask but also resembles the mask Gail wore in the original Sin City story and A Dame To Kill For.
- Switching P.O.V.: Every chapter has a different narration.
- Teeth-Clenched Teamwork: Anytime Batman has to team up with a Sin City character. Averted with Miho, who actually seems to enjoy working with him.
- Villainous Crush: As usual, the Joker all but admits that he's in love with Batman. He mentions that he missed Bats while he was visiting Sin City and even decides to create a literal bat family by injecting victims with a new serum that turns them into Blood Knights. He then dresses them up as Batman and Batwoman. Later, he decides to make "children".