Til Death Do Us Part

Following an unsuccessful yacht robbery, Harley Quinn is sent to Arkham Asylum; though she firmly believes that her boss and lover Joker will break her out. A year later her BFF, Poison Ivymanages to get Harley out during a prison break and tries to convince her that Joker does not love her. Despite Ivy's support, Harley's attempt to break up with Joker fails after he sweet-talks her into staying with him. The Riddler, who also escaped Arkham, provokes Joker in sending Harley to kill him. Riddler captures her and Batman before threatening Joker to save one while the other gets submerged in acid. When Joker ultimately chooses Batman, Harley finally realizes she never meant anything to the former. It's also revealed the death trap was devised by Ivy and Riddler to drive that point home. Following a costume change, Harley officially breaks up with Joker and declares her intention to make a name for herself in the criminal underworld.