Margot Robbie reprises her role as Harley Quinn in this action adventure spin-off of 'Suicide Squad' (2016). After breaking up with the Joker, Harley is enjoying her new-found independence in Gotham when she runs into trouble in the form of crime lord Roman Sionis aka Black Mask (Ewan McGregor) and his right-hand man Victor Zsasz (Chris Messina). When orphan Cassandra Cain (Ella Jay Basco) steals one of Roman's diamonds, he tasks Harley with finding the young thief. However, it's not long before she teams up with Dinah aka Black Canary (Jurnee Smollett), vigilante Huntress (Mary Elizabeth Winstead) and GCPD officer Renee Montoya (Rosie Perez) to turn the tables on Roman.