The Joker has escaped Arkham, with help from Psychiatrist Harleen Quinzel whom he turn into Harley Quinn. Now he seeks revenge by destroying everything he holds dear and driving Commissioner Gordon mad. Batman, Nightwing and Robin, also Batgirl may have a chance to beat him. With Batman being pushed to his breaking point. Meanwhile Jason Todd discovered that his mother is still alive. Call it Batmanβs darkest chapter.