Heroic Hollywood got new details regarding the plot, villain, and other characters that will make an appearance. The following is the basic plotline that Zack Snyder and David Goyer apparently pitched to Warner Bros. after Man of Steel was completed. You might consider this a SPOILER, but it’s so incredibly early in the development process that anything can change between now and when the movie is actually released.
As the previous report said, Brainiac might be the main villain of the movie, and according to the latest info he will be looking for the genetic codex of the entire Kryptonian race. This is the same thing that General Zod wanted to get his hands on in the first Man of Steel movie. The site goes on to say that “he is not trying to retrieve the codex from Superman. You see folks there was another Kryptonian survivor.”
Who is that other Kryptonian survivor? Well, that would be none other than Supergirl. Apparently she’s always been a part of the plan. According to the report, David Goyer‘s prequel comic said that “Kara Zor-El was the most promising daughter of the House of El.” That prequel told Kara’s story “as she nears completion of her training. She intended to become a member of Krypton’s ‘Explorers Guild’; citizens tasked with searching the cosmos for suitable planets, and triggering terraforming projects to make them inhabitable to Kryptonians.”
They go on to say that the sequel won’t just introduce Supergirl, but it will actually focus on her just as much as it will focus on Superman. This is apparently one of the main aspects of the project that got Miller’s attention in the first place, and it’s the main reason why he’s looking at directing it.
All of this leads to something, and that is to the creation of Bizarro! To help obtain the codex from Kara, Brainiac creates Bizarro to hunt her down.