Birds of Prey, the next film on the docket from Warner Bros. and DC Films, will star actress Margot Robbie as Harley Quinn. This particular incarnation of Black Canary will be the Dinah Laurel version of the character, who inherited the superhero alias from her mother. She's a detective who recently became a masked crimefighter after adopting the Question persona.
Like Canary, Cassandra Cain is a formidable martial artist. In previous interviews, Margot Robbie insisted she wanted a more diverse cast, and if they are sticking to the comics, then Montoya is of Latin descent and LGBTQ, and Cassandra Cain is Asian, so this gives credence to the current rumors.
The daughter of assassins David Cain and Lady Shiva, Cassandra is trained to be the world's greatest assassin, but ends up mute, illiterate, and with limited social skills. She also happens to be one of the best martial artists in DC Comics, holding her own against the likes of Bronze Tiger, Deathstroke, and even Batman. She's eventually taken under Barbara Gordon's wing and is accepted into the Batfamily - taking on the mantle of Batgirl after Barbara.
Some months back it was reported Barbara Gordon would be introduced in this film before her Batgirl solo movie, but it could be that we still see Babs in her Oracle identity. It was in Gotham Central that Renee is outed as a lesbian, and her character goes on to become one of the most popular LGBT characters in the Batman comics, especially when she begins appearing in the Batwoman comics. She doesn't have any superpowers, though she did don a disguise as the enigmatic Question for a brief stint. According to TheWrap, the film is centered on a revolving group of female heroes fighting against several villains, including an unknown character from Batman's rogue gallery. In the comics, the Birds have usually been led by Barbara Gordon as Batgirl, or sometimes as Oracle.
Birds of Prey, directed by Cathy Yan, has not been given a projected release date.