Harley and Ivy go undercover as college students to take down Riddler, who's made himself dean of the local university with sinister plans for students.
While Bruce is frustrated by his inability to fight crime because of his injuries, Bane insists that Two-Face make him a full partner now that Harley has killed the other members of the Injustice League. Batgirl emerges from the shadows to fight crime in Gotham, and carry on the Bat tradition - whether Batman wants her to or not.
When Harley and Ivy spot a seemingly sane Joker, they debate whether people can change at their core, revisiting a flashback about Harleen Quinzel's first day at Arkham Asylum.
Two-Face has Harley and Ivy sentenced to life in Bane's prison, which is a giant pit in the ground; Jim Gordon and Batgirl vow to take back the GCPD headquarters from Two-Face.
Alone on Christmas Eve, Harley reconnects with a now-sane Joker and heads to Wayne Tower, where their dinner is interrupted by an escaped Riddler and ParaDemons.