Supergirl "Plot Hole" Explained: Why Kara Didn't Just Take Krypto To A Yellow Sun

Published Sep 12, 2026, 7:15 PM EDT

Shawn S. Lealos is an entertainment writer who is a voting member of the Oklahoma Film Critics Circle. He has written for Screen Rant,  CBR, ComicBook, The Direct, The Sportster, Chud, 411mania, Renegade Cinema, Yahoo Movies, and many more.
 

Shawn has a bachelor's degree in professional writing and a minor in film studies from the University of Oklahoma. He also has won numerous awards, including several Columbia Gold Circle Awards and an SPJ honor.

He also wrote Dollar Deal: The Story of the Stephen King Dollar Baby Filmmakers, the first official book about the Dollar Baby film program. Shawn is also currently writing his first fiction novel under a pen name, based in the fantasy genre.

To learn more, visit his website at shawnlealos.net.

There is a moment in Supergirl that many people are convinced is a plot hole, but the moment is actually explained in the film's dialogue. Supergirl is the 2026 DCU movie that follows Kara Zor-El (Milly Alcock), Superman's cousin, as she deals with the trauma from watching everyone she loves die. At the same time, she sets out to help a young girl named Ruthye (Eve Ridley) seek vengeance after her parents were murdered in front of her.

Directed by Craig Gillespie and based on a script by Ana Nogueira, Supergirl ended up as a box office bomb when released in theaters, making only $126.4 million on a $170 million to $186 million budget. It also has a lower 53% Rotten Tomatoes score, although its 72% audience rating is higher. Now, Supergirl is available to stream on HBO Max, and audiences who missed it in theaters can see for themselves if the movie deserves its reputation as a flop.

One scene that might make more sense upon a rewatch is when Supergirl has to leave Krypto dying on a planet with a red sun while she searches for the villain, Krem of the Yellow Hills (Matthias Schoenaerts), who carried the cure for the dog with him. There are some who think this is a plot hole because Supergirl could have taken Krypto to a planet with a yellow sun to save him. However, that isn't the case.

Kara Couldn't Move Krypto Without Serious Risk

Supergirl not taking Krypto to a planet with a yellow sun isn't a plot hole because the movie's dialogue explicitly explains that she couldn't do this. In the movie, Krem of the Yellow Hills shoots Krypto with a poison dart, and the dog falls instantly. When Supergirl takes Krypto to a local doctor on the planet, she learns about the poison and finds out that Krem has the only antidote. Krypto only has three days to live.

The supposed plot hole suggests that Supergirl could have flown Krypto to a planet with a yellow sun, and he would have instantly revived. However, when she actually suggests that exact thing in the movie, the doctor explains that Krypto is so badly injured that attempting to fly him through space to a galaxy with a yellow sun will kill him quicker than the three-day wait.

This moment isn't a plot hole because Supergirl explicitly says that is what she wants to do, but then learns it won't work. Luckily, she is able to get to Krem and get the antidote back to Krypto before it is too late, saving her beloved dog.

How Supergirl Changed Krypto's Poisoning From The Comics

The movie makes several changes from Supergirl: Woman of Tomorrow by Tom King and Bilquis Evely. One of the changes involves Krypto. On the surface, both stories play out the same, with Krypto charging after Krem of the Yellow Hills and getting shot by a poison dart. Krypto falls in both versions. Supergirl admitted that he was dying, and she had to find Krem to get the cure.

However, in the comics, Supergirl was lying. She lied to Ruthye, making Ruthye think that she was only coming with her so she could save Krypto. In reality, Supergirl went with Ruthye to stop the girl from doing something she would regret by killing Krem. By lying about Krypto's condition, she was able to help Ruthye without the girl knowing her true intentions. Krypto was saved through actual medical treatment in the comics, although the reader didn't know that until the end either.