DC's Suicide Squad. While that film didn't receive much critical or fan praise, it earned $746.05 million worldwide, making it a financial success. A bright spot of the film was Margot Robbie's Harley Quinn, and at one point, numerous spin-offs surrounding Harley were in development. One of those spin-0ffs was Gotham City Sirens.
Gotham City Sirens was reportedly going to focus on Harley and a team of female villains including Poison Ivy and Catwoman. The Suicide Squad instead.
While speaking at a Television Critics Association press event (via Gotham City Sirens was no longer in development, but Ayer's new comments suggest that while nothing is coming in the near future, it could happen eventually.
Robbie's involvement with Birds of Prey and The Suicide Squad are probably factors in Gotham City Sirens' delay. She would be a major draw for the film due to both her popularity as an actress and Harley's popularity as a character. It's likely Robbie will stay within the DC universe for a while, but no appearances have been confirmed beyond The Suicide Squad.
Meanwhile, fans disappointed the The Batman, which recently began filming and exists outside of the DC Extended Universe where Robbie's Harley resides. DC has a packed slate for the next few years, and if Gotham City Sirens picks up development any time soon, it likely won't be released until at least 2023. Perhaps Harley's role in her next two films will lead to the formation of the group. For now, though, it looks like she's sticking with the Birds of Prey.
Source: /Film
