When part of Gotham is turned into a private reserve for criminals known as Arkham City, all hell is sure to break loose, and the Dark Knight is the only one who can stop it.
After the incident at Arkham Asylum Mayor Sharp has walled off the middle of Gotham and turned it into a prison. Now gangs rival and war inside the prison and Mayor Sharp has put Hugo Strange I charge
- When you go to Two Face's courthouse and you enter the back way; you can go down to the cell next to the Calendar Man's cell. When you're in that cell turn on detective mode, look up (make sure you are under them), and punch. When you do that they somehow notice you and run through the door and come to fight you.
- An Easter egg/reference relating to The Scarecrow can be found on a barge in the docks area. When on the barge, use the sequencer gadget to solve the code "City of Terror". A panel opens. Once inside, you are in a room filled with neon bug zappers. At the end of the hall, there is an unconscious inmate sitting in a chair. Upon zooming in on him, he is startled awake and gives a loud shriek. He goes back to sleep. It is assumed that he is a victim of The Scarecrow's experiments.
- It is heavily implied at one point in the game that Harley Quinn is or was pregnant. This is suggested by examining Harley's costume on a dummy and panning down to the floor. At the dummy's feet is a box reading "Fruitful Endeavors pregnancy test". Lying beside it is a positive test.