Shazam has been out for almost a week at this point, which means it's time to talk about some major spoilers. If you haven't seen it yet, don't keep reading! Unless you don't care about Shazam spoilers, in which case, have at it.
In the world of the DC cinematic universe, Shazam is actually fairly sparse as far as connections to other DC heroes. There's no major climactic cameo like Wonder Woman showing up in Batman v. Superman, and no heroic team-up like the Justice League (unless you count the big twist in the climactic fight with Dr. Sivana).
There is one DC character cameo, and it's played entirely for laughs: at the end of the movie, when Superman shows up during Freddy's lunch hour at school. It's payoff for the bit earlier where Freddy bragged that he's friends with Shazam, and seeing Clark Kent from the torso down only somehow makes it even funnier, as it lets us focus on the other characters' reactions.
But the scene almost turned out very differently, Shazam director David Sandberg told GameSpot: They initially tried to get Superman actor Henry Cavill to appear in full at the end of the movie.
"It was originally written as a scene where he sits down and he talks to the kids a little bit and kind of ends with Freddy going, 'I have so many questions,'" Sandberg said. There was even dialogue written--"They sort of joked around...something about aliens or something," Sandberg struggled to recall.
"It wasn't actually that fun, which is why this is so much better," the director continued.
Sandberg said Cavill's cameo didn't work out for scheduling reasons. "We could only be in that school in Toronto for a certain date, and we just couldn't work it out," he said. But he still wanted to have the payoff that Superman's appearance creates, so he brainstormed other ways to do the scene. "We tried shooting it the way we did, and I thought it worked great," the director said. "It seemed actually funnier than the scene we had written, because you see him come in, you see Freddy's great reaction, and you just hard cut to the end credits. It just makes me laugh, you know? So, in some ways, it kind of worked out for the best."
"But it would have been great to actually work with Henry Cavill," Sandberg added.
Cavill's part in the larger DC universe has been up in the air lately, as rumors have mounted since last year that the actor won't return to the role of Superman. We've yet to get a concrete answer on that, and we'll likely never know for sure whether those tensions had an effect on Cavill's would-be Shazam cameo. In the end, we find it easy to agree with Sandberg's assessment: The scene, and the movie as a whole, turned out just fine.