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This flash animated series had three seasons of ten episodes each. (Episodes were a few minutes long, so each season was roughly a half hour.) The series aired between 2000 and 2002, and I think I must have been aware of it at the time, though I don't remember for sure. I might have even seen a bit of it back then, but watching it years later (late 2015/early 2016) as a bonus feature on the Birds of Prey DVD, nothing really seemed familiar. I should mention that on the original website (which no longer exists), there were flash games accompanying the episodes, as well as a minor interactive element within the episodes themselves. Those options don't exist on the DVD, but some of the sites I linked to above will let you watch episodes online, which does allow you to play the games or do the interactive stuff. Also, the main characters' voice actors were the same as in Batman: The Animated Series. And I should mention that, since the show was made in the early days of flash animation, its look didn't start out great (though it was okay). And the animation did improve, from season to season.
Anyway, the first two seasons were mostly stand-alone, humorous stories. They featured various combinations of female characters, including Poison Ivy, Harley Quinn, Catwoman, Batgirl, and to a lesser extent Zatanna. The third season was a more serious, ongoing story. It began with the disappearance of all the men in Gotham, which meant Commissioner Gordon was replaced by an acting commissioner named Caroline Greenway, who didn't seem upset about the men's disappearance, and had no interest in working with costumed vigilantes like Batgirl. However, a couple of people in the police department, Detective Montoya and a secretary named Dora, both offered some help. The men are returned to Gotham at the end of episode 4, but there's still something strange going on, which Batgirl continues to investigate. Also, Catwoman, Ivy, and Harley are all blamed for the disappearance, though Batgirl knows they're innocent. She also receives some help from a detective named Selma Reesedale, who had disappeared (and later returned) along with the men. (It turns out she was a transsexual, but that's not really important to the plot. It's kind of interesting to see such a character so casually exist in a show from fourteen years ago, particularly to be watching this after 2015. Though I'm not sure how trans people would feel about this... the implication that she's really still a man. But I reckon it's only the technology used to make the men disappear that's making that judgement, and I have no idea how such a weapon would work. It is, after all, based on comic books, which don't require any kind of realism. And I suppose DNA can't be changed, in any event.) But I digress. Um... well, Batgirl eventually solves the case; it seems as if the disappearance of all the men was really just a distraction for something else. But I don't want to spoil what it was really about, or who the mastermind was.
Well, I'm happy to have finally seen the series. The whole thing was enjoyable, both the comical first two seasons and the more mystery-based third season. Also, there was a 5-issue Gotham Girls comic book miniseries in 2003 (though I didn't read it until 2022). There have also been other comic books in a similar vein, including "Harley & Ivy" and Gotham City Sirens. And... I'm not sure what else I can say.