"The Joker's attack on Arkham Asylum left the long-standing Gotham establishment in ruin, most of the patients killed or missing, and only a handful of surviving staff: a few nurses, a gravely injured security guard, and one doctor. In the chaos of the assault, it is believed that several of the asylum's patients escaped and scurried off into the dark nooks and crannies of Gotham City. Now, these Arkhamites walk among us, and it's up to the ... one remaining doctor, Jocasta Joy, to round up her former patients"--
