Abstract In Gotham City, the Joker breaks up with Harley Quinn and without his protection, several criminals that have a beef with her hunt her down. When the teenager Cassandra Cain pickpockets a diamond that has the account numbers of a fortune from the gangster Victor Zsasz, who is the right-hand of the powerful criminal Roman Sionis, he put a contract on her. Harley Quinn, Police Detective Renee Montoya, Helena "The Huntress" Bertinelli and Dinah "Black Canary" Lance team up to protect Cassandra /