David Ayer will return to helm the highly anticipated DC film, "Gotham City Sirens."

Consisting of Harley Quinn, Poison Ivy and Catwoman, the Sirens is a group of villains that are frequent foes of the Bat family in the DC comics. The team-up film will be piggy-backed by Warner Brothers and is seen as one of the most entertaining teams in the DC Cinematic Universe. 

In the film, Margot Robbie's Harley Quinn will star as the leader of the team. Other than Robbie, no other character for the Sirens has been cast. Prior to "Suicide Squad," it was rumored that Robbie was in negotiation with Warner Bros. for a solo movie starring Harley Quinn. However it was not until recently that David Ayer confirmed that both Poison Ivy and Catwoman would join Harley Quinn in the film adaptation of the "Gotham City Sirens."

Now that the film has been confirmed, many wonder who could be cast to fill the two other roles. Poison Ivy has only been seen once on screen before, played by Uma Thurman in "Batman and Robin." On the other hand, Catwoman has been played several times by actresses like Michelle Pfeiffer, Anne Hathaway and Halle Berry. According to reports, Hathaway has expressed interest to reprise her role as Catwoman, but many speculate that the "Gotham City Sirens" production will look for someone entirely new to portray the character.

As of now, David Ayer's Twitter feed is teeming with DC fans suggesting casting for the film. Since the director has not even announced a release date for the film yet, it looks like it will be some time before fans even get hints of the actresses who will play the two remaining unfilled roles.