Okay so today we found out that Jena Malone has a confirmed role in Batman vs. Superman, but we don't know who. Well, let's look at the few clues we have:
We see pictures of Jena Malone talking to Zack Snyder around the set of Batman vs. Superman, implying she has something to do with the film.
Then Jena posted this on her Instagram. Red hair? Everyone immediately thought of Carrie Kelly, the female Robin from The Dark Knight Returns, which takes palce on Earth 31. And this works because Ben Affleck admitted last week that Batman vs. Superman was heavily based on The Dark Knight Returns. This could just be because of Bruce's age and the Batman vs. Superman thing, but when you want proof, you find it anywhere.
Personally, I don't think we'll see her Carrie Kelly. She's too old. But I do have and idea on who she can be...
Yes. The manic leader of the Suicide Squad. Think about it: Jena has the perfect mischevious eyes, all sinister and angular. She has the charm, and the craziness. Did you see her Catching Fire performance? She was truly her character. And half of Harley Quinn's hair is red, so...
Also, Suicide Squad is coming 5 months later, and I highly doubt Warner Bros. would just go ahead and let a random team take a movie. They need an introduction, and Batman vs. Superman, aruguably the most anticipated superhero at the moment, is the best place to introduce her.