Before watching the movie:
Similar to how the Batman franchise spun off Catwoman, after three Christopher Reeve movies, the Superman franchise spun off Supergirl. However, while Catwoman was basically made because the next proper Batman movie was in development hell, my understanding is that Supergirl was a pure spinoff attempt riding on the success of Superman. While Catwoman is generally considered awful, it was followed by the acclaimed Dark Knight Trilogy, and I get the sense Supergirl is considered okay but forgettable, and it was followed by Superman IV.
I know exactly what to expect from the plot because this is the introductory movie of a superhero, which has been required to be the rote origin story for around 40 years, if not longer. As for a villain to slot in, I’m not sure what to expect, since I don’t know of Supergirl having any villains that are “hers”. I’m really not that familiar with her at all besides the basics of her relationship with Superman, so maybe I won’t have lore bogging down my enjoyment.
After watching the movie:
In Argo City, a colony of beings wielding magical technology are secreted in a dimension of “Inner Space”. Kara Zor-El is a young girl who has befriended an older artist, Zaltar. While playing with Zaltar’s wand, Kara accidentally flings Argo City’s power source, the Omegahedron, into Outer Space, and sets off after it in an interdimensional pod before her parents can stop her. Kara arrives on Earth transformed by the journey into Supergirl, but the Omegahedron has already been found by Selena, a witch with world domination inclinations. While trying to find the Omacguffinhedron, Kara must blend in on Earth in the guise of orphaned boarding school girl Linda Lee, who may one day get to actually meet her cousin Clark Kent.
This leans on the established material in just the wrong amount. It’s not close enough to be in the same league with its parent franchise, yet not far enough away to be a fresh take. It feels like a cheap knockoff. This isn’t Superman-adjacent, it’s Superman methadone, featuring the estranged cousin of Superman, Lucy Lane: Lois’s Kid Sister, and Jimmy Olsen: The Only Character From The Others To Barely Appear In This Film. I think we’re left to just know or assume that the people of Argo City are Kryptonian refugees from the destruction of their planet. Superman’s (physical) absence is explained as him being on a mission of peace to a faraway galaxy in a dubbed radio newscast. I might have been more able to accept the assertion that Kara turning Super was because of the nature of her journey between dimensions, but she came out the other side having had her clothes changed from her Argo City diaphanous poncho thing into her superhero uniform that looks nothing like it.
On the other hand, the use of the Phantom Zone was actually rather smartly handled for the most part, both in the structure of the narrative and in how it allows us to see more of Peter O’Toole’s Zaltar. He and Peter Cook, who played Nigel the warlock/girls’ school math teacher (???) were the best parts of the movie. I also think Argo City was more fully realized than Krypton was, even on an obviously much smaller budget, and also made clear from the outset that this was going to be a much more fantastical take (so much as you can call a man who flies and has heat vision hard sci-fi).
Unfortunately, the fantasy angle seems to give the filmmakers an excuse to not make any sense. After leaving Argo, it alternates between boring and insane. It takes quite a long time on Kara settling into boarding school life and then Selena does bonkers magic she might or might not actually understand. She was a witch before finding the Omegahedron, but she uses it to amplify her magic occasionally, and her spells usually go wrong even without channeling extraterrestrial power. Selena spends most of the movie obsessing over a handsome landscaper named Ethan she gave a love potion to who imprinted on Kara instead of her, and then even when the spell is broken he reveals he genuinely loves Kara when I’m pretty sure they hadn’t even met before he was under the influence.
Looking over the production history, it was in fact rushed from start to finish in under a year after Superman III, so in retrospect, I can see how it may have been written in the cutting room. It’s also unfortunately a very female-driven story with a male creative team (director, writer, producer), something that would have had greater protest if made now. I don’t regard this as quite as terrible as my first watch of Superman IV, and I’m sure a rewatch knowing how insane it gets would improve my reaction to it. But it’s ultimately just poorly written and cheaply made. There are better superhero movies, and better treatments of Supergirl out there, I’m content to let this be what it is and go enjoy the others.