We learned recently that Margot Robbie pitched Birds of Prey as a "R-rated girl gang film", and it sounds like Warner Bros. was on board. However, according to Robbie in an interview with MovieFone, they weren't always on board, because she's been working on this for three years. It also took some time to find the right director, and once they did Robbie knew that they were golden.

"It was very important," Robbie explained. "I've been working on this for three years now and, from the beginning, I wanted to make an R-rated girl gang film and we needed a female director. The best director always wins, whether male or female, it's more about who understands the character the best. But given how few opportunities female directors get, particularly on these big budget films, I thought it was our duty to put more effort into exploring female directors than male ones," Robbie said. "Definitely not to exclude male directors, but put more effort into exploring female directors. So we looked at both male and female directors and Cathy was the best."

Robbie went on to say that this movie has been her focus and that she doesn't know anything about the other rumored Harley movies, including Gotham City Sirens and the Joker and Harley movie.

"I pitched it to her actually," Robbie told us. "I said, 'I want to make a girl gang, R-rated film that Harley is a part of.' And we started working on it from there. Meanwhile, over the course of the next few years, the studio was exploring other Harley Quinn spin-offs. But I was not a part of those versions, I was always focused on this one with Christina. I know that they were exploring 'Gotham City Sirens' with David Ayer, and I know they were exploring a Joker and Harley Quinn movie, and they were exploring doing I don't know what else. I wasn't a part of those. I was focusing on this. I kept presenting it to the studio until they felt it was at a point where they were ready to do it. And now we're all in."

What does that mean for those other Harley Quinn projects? Who knows. The DC Extended Universe is in such flux these days that things could change any day now. It does sound like Robbie is very passionate about this movie, and a production with passion behind it is always interesting if nothing else.