Although Joker sidekick/love interest Harley Quinn was teased in the last season of Arrow, she's not going to become a big part of The CW series. Why? In an interview with Comic Book Resources, executive producer Andrew Kreisberg says he wanted to do more with Quinn, but apparently Warner Bros. may have future plans for the character.
There are very few things we've asked DC Comics for that we haven't gotten. That was something you asked for, and what you saw is a compromise that Geoff Johns and I came up with. To even get that much was a thrill for us. I know that they may have other plans for her, but it was certainly an Easter egg that thrilled us. But the Suicide Squad will definitely be back. Whether we see the 'deranged female killer' we saw before, we'll have to wait and see.
So what might those "other plans" be? Some believe Warner Bros. might still be interested in doing a Suicide Squad movie, and since DC's movies and television series don't exist in the same universe, there could very easily be two different versions of the antihero team.
But if that's the case, why not have Harley Quinn appear in both? The only reasons I can think of is maybe Warner Bros. and DC are also looking into doing a Suicide Squad TV series, or something else on television with Harley Quinn as one of the lead characters. What do you think are Warner Bros. and DC's plans for Harley Quinn?
Season 3 of Arrow will premiere on The CW on October 8, 2014.