I understand why James Gunn’s Brightburn didn’t light up the box office. Despite it being a masterfully done parallel to Superman, it’s bleak AF. However, there was an alternate ending being kicked around of a “super-girl” either saving the day or fighting the evil Brandon in the film’s climax.
Per Bloody Disgusting:
Director David Yarovesky’s Brightburn tells the origin story of Brandon Breyer, a kid with super-powers and strict orders to use them for evil rather than good. One of Brandon’s first acts as a super-villain comes when he completely shatters the hand of a classmate named Caitlyn (Emmie Hunter), whose mother eventually becomes Brandon’s very first kill.
Weirdly, despite Brandon’s obsession with her, Caitlyn soon thereafter disappears entirely from the movie, one of a couple storylines in the film that seems to have been shaved off in the editing room. Brightburn sets up Caitlyn as the apple of Brandon’s eye, but aside from a brief visit to her bedside after he breaks her hand, we never see her again.
So what happened with Caitlyn? Well, an alternate ending was going to show us. As Yarovesky explained to Collider, the idea was conceived but never actually filmed.
Unfortunately, the final version of Brightburn unceremoniously writes out Caitlyn and the whole storyline of Brandon being obsessed with her, but here’s hoping a potential sequel revisits the character and allows for her to become a sort of superhero on a quest for revenge. After all, not only was she maimed by Brandon, but her mother was killed by him as well.
If that’s not a superhero origin story in the Brightburn universe, I’m not sure what is.