Over the last few years, Supergirl has been getting a lot of attention on screen thanks to her TV series on The CW, but yesterday it was announced that Kara Zor-El might be heading back to theaters in the near future. More than three decades after the Helen Slater-led Supergirl movie was released, it was reported that Warner Bros and DC have a new Supergirl movie in the works, with Oren Uziel penning the script. The DC Extended Universe's Kara was previously depicted in the Man of Steel prequel comic book, but that's not necessarily canon anymore, so it's anyone's guess what this version of Kara is actually like on the silver screen.
Like most of the DCEU projects in development, there's no guarantee just yet that the Supergirl movie will move from script into a full-blown production. That said, if it does get off the ground, here are some of the comic stories starring the Girl of Steel that make for good source material for this movie to use.
The Supergirl From Krypton
After she died during the Crisis on Infinite Earths event, Kara Zor-El only appeared sporadically in the DC universe until 2004, when she was reintroduced in the Superman/Batman series. In this continuity, rather than their familial relationship just being a cover, Supergirl and Superman were actually biological cousins, and when she landed on Earth, not only did Kal-El help her acclimate to Earth, she was also mentored by (an initially distrustful) Batman and Wonder Woman. This tale was previously adapted into the 2010 animated movie Superman/Batman Apocalypse, and while a completely faithful adaptation probably wouldn't work for the big screen given that it'd be difficult for Batman and Wonder Woman to be involved, as long as Henry Cavill's Superman is at least around, with some creative shifting, this could serve as a cool origin story for Kara.
Supergirl And The Legion Of Super-Heroes
Like Superman, Supergirl has a long history with the Legion of Super-Heroes, a team of young superpowered beings who hail from different worlds in the 31st century. In fact, during Mark Waid's run on the Legion of Super-Heroes comic series in the 2000s, the title was changed to Supergirl and Legion of Super-Heroes to establish that Kara had joined the team. It might seem like a big leap for Supergirl's first movie to bring in a whole team of colorful superheroes, but this would be a fun way to separate Kara's adventures from what Superman is doing in his own corner of the DCEU. Plus, it was reported a few years back that Warner Bros and DC were considering making a Legion of Super-Heroes movie. It's doubtful that will happen now, but with certain Legion members having already appeared in live action on Smallville and the Supergirl TV series, giving them a platform in the DCEU is the next step towards boosting their profile for the public, though not so much that it takes Kara out of the spotlight.
Last Daughter Of Krypton
The New 52 reboot saw most of DC's characters' histories being changed, and Supergirl was no exception. Once again, we were reintroduced to Kara Zor-El as she lands on Earth for the first time. Aside from her costume being redesigned, this version of Kara was a lot more headstrong than her previous incarnation, preferring to learn Earth's ropes on her own. If Henry Cavill doesn't show up as Superman in the Supergirl movie, this story would probably be the best way to tackle Kara's DCEU origin, as it highlights Kara's independence and makes her acclimation to our world more interesting.
The opening arc of Supergirl's new solo series following her reintroduction of the pages of Superman/Batman saw Kara getting the hang of being a superhero, but as is usually the case, this process is rarely a simple one. The adventure saw Kara being split into two beings by black kryptonite, giving readers a good version and bad version of her. Dark doppelgängers, whether they're clones or hail from a different universe, are one of the kookier superhero plot tropes, but for the Supergirl movie, this could work if Kara already has a little experience under her belt. Power also delved into some of Kara's past on Krypton, so this would be a good way for us to learn more about what Kara's life was like on her homeworld beyond what was shown in the Man of Steel prequel comic.
Supergirl: Being Super
Here we have yet another candidate for an origin story adaptation, but Being Super is a more grounded, young adult take on Kara becoming Supergirl. In this miniseries, Kara has been on Earth for years living as a regular teenager, but on her 16th birthday, her powers awaken, forcing her to take her first steps into the superhero life. If we assume that the Man of Steel prequel comic is no longer considered canon, then this could be a cool way to establish Kara on the DCEU's Earth. Rather than her arriving on our world at the start of the movie, she arrived years earlier, perhaps around Man of Steel, and as we watch her develop her special abilities in the present day, flashbacks would reveal the circumstances in which she came to Earth.