Joker is dead. And all crimes in Gotham seemingly came to an end with that power vacuum created by his death. However... soon enough someone would begin filling it. One peaceful night at a diner turned horrifying due to a chemical attack turning people insane with fear. And not long after, the people gathered outside saw Scarecrow broadcasting a message on a billboard that they should leave Gotham lest he would unleash a chemical weapon on whoever would remain...which would engulf the entire city. What he released at the diner was merely a tiny fraction of that. And, in a panic, every citizen took buses to get out of the city until few good people remained in Gotham.

You unfortunately missed the last bus and suddenly found yourself trapped inside Gotham with criminals, thugs and even villains including Two-Face, Riddler, Penguin, Harley Quinn, Poison Ivy and other villainous rogue gallery members that Batman has faced or is about to face, excluding the deceased Joker. They were now in control, killing cops and even civilians and pretty much painting the town red. Chaos and crime ran rampant so you had to be careful not to be swallowed by it. Be careful now. Don't rely on Batman saving you from trouble too much.

You were inside an apartment when you noticed a brick hit your window and shattered while you heard laughter outside. You peered out, without being seen, and saw some thugs painting the town red in all the lawlessness.