Superman ends with Kal-El returning to the Fortress of Solitude, where he's soon joined by his cousin, Supergirl. She shows up to retrieve Krypto and is clearly inebriated as she lets the mischievous pooch throw her around.
The Man of Steel tells "Gary" (a.k.a. Superman Robot #4) that Kara travels to planets with a red sun to get drunk, and the stage is then set for next year's Supergirl movie from filmmaker Craig Gillespie. However, some longtime DC Comics fans didn't like the way the character was introduced, making her cameo surprisingly divisive.
Those of you who have read Supergirl: Woman of Tomorrow will be aware that it features a very different take on the Maiden of Might, and for James Gunn, her appearance was also an important part of Superman's story.
Talking to Entertainment Weekly, he explained, "The main reason for Kara showing up is to show that Superman not only risked his life to go save a dog that was his dog, that so many of us would do, he was watching the dog for somebody else. The dog's a pain in his ass. He didn't want to take that dog. She's off being irresponsible."
"He doesn't want to have to watch a dog. He's having to save the world every two seconds. And even still, he goes to the ends of the earth for that dog."
"To me, that's one of the most touching things in the movie. Earlier, when Lois says, 'It's just a dog,' and he says, 'Yeah, not even a very good one, but it's probably scared,' it just shows you the depths of his empathy," the filmmaker continued. "I find that so touching. Then, when you find out at the end, it's not even his dog; she just left it with him."
Supergirl wasn't Superman's only cameo, of course, as Peacemaker also shows up on a talk show which sees him slate Metropolis' protector and other heroes who believe they're more jacked than he is.
After Gunn reiterated recent remarks about pocket universe technology also playing a key role in Peacemaker season 2, he confirmed that John Cena "would've been in there no matter what."
He added, "I like the idea that he's going on this incendiary talk show, and he's one of these assholes that would be on that show. Cleavis Thornwaite [Michael Ian Black]. I haven't heard many shoutouts, but to me, he's perfect in the movie. He's perfect. He shows up again, Cleavis Thornwaite, in Peacemaker."
Later, the DC Studios co-CEO addressed his philosophy when it comes to cameos:
"A cameo is fine as a cameo, where somebody appears for two seconds, and it's fun, like with Peacemaker, or how Stan Lee would appear in the Marvel movies. I don't like cameos when it has nothing to do with the story or the plot, and is anything more than a line or seeing them for two seconds. There seems to be, in some superhero movies, cramming other people in because people like seeing these characters together."
"I don't really love that new tradition. They need to have a story reason for being in the movie. I wouldn't have put Hawkgirl and Mr. Terrific and Guy Gardner in there if they were representing something different than to what Superman represented, and if they didn't have the role in the story that they did, where they too are inspired by Superman."
Superman is now playing in theaters. Peacemaker season 2 premieres on August 21, and Supergirl swoops into theaters on June 26, 2026.