'Black Adam' has 1 must-see end-credits scene. Here's what it may mean for the future of DC movies.

• Warning: There are major spoilers ahead for "Black Adam."
• There's one extra scene after the first batch of credits roll during Dwayne Johnson's DC movie.

If you head out to see "Black Adam" this weekend, don't leave the theater as soon as the movie ends.

There's one extra scene during the credits featuring the return of a beloved superhero who fans have been hoping to see for some time on screen.

If you stepped out too early, don't worry. We have you covered.

Here's what you should know about the scene everyone will be talking about.

What happens: A Justice League member pays Black Adam a visit

The scene opens in the evening with a drone flying down to meet Black Adam (Dwayne "The Rock" Johnson) at the location where he crushed his throne at the film's end.

A projection appears out of the top of the drone and we see the familiar face of Amanda Waller (Viola Davis), a government official and the Task Force X/Suicide Squad commanding officer.

"OK, Black Adam. My name is Amanda Waller. Congratulations, you have my attention," Waller's live projection says. "This is gonna be your only warning. You don't want to stay in my prison that's fine. Kahndaq is your prison now. You step one foot outside of it, you will not live to regret it."

Black Adam calls her bluff with a retort.

"There's no one on this planet that could stop me," Black Adam tells her.

Waller tells the antihero she could call in a favor and send in people who aren't from Earth.

Black Adam gives a small smile before telling her: "Send them all."

As Waller says, "As you wish," Black Adam explodes the drone to bits.

A dark figure then flies down into the cloud of smoke from the small explosion.

"It's been a while since anyone's made the world this nervous," a shadowy figure says from behind the smoke.

Henry Cavill's Superman then steps forward from the shadows to the tune of John Williams' Superman score instead of Hans Zimmer's "Man of Steel" theme.

"Black Adam. We should talk," he says.

The scene moves to Black Adam's stern face before cutting to black.

We have Johnson to thank for bringing Henry Cavill back as Superman

Cavill's big reveal may not have been as big of a surprise as Warner Bros. hoped. The mid-credits scene began leaking online a week ahead of the film's release and could easily be found across social media.

But Cavill's return as the Man of Steel is a huge deal. Aside from 2021's "Zack Snyder's Justice League," we haven't seen Cavill as the Man of Steel since 2017's "Justice League."

Cavill was supposed to cameo in 2019's "Shazam!" featuring Zachary Levi as Black Adam's comic nemesis, but entertainment journalist Grace Randolph reported that it fell apart when the actor wasn't paid extra money to return.

Additionally, Cavill reportedly wanted a say in the director for a potential "Man of Steel" sequel. Instead, fans awkwardly saw a stunt double dressed as Cavill's Superman from the neck down in the finished film.

Apparently, Johnson advocated bringing Cavill back in his film. The two share a manager in Dany Garcia, Johnson's ex-wife.

According to The Hollywood Reporter, Johnson approached now-former DC films president Walter Hamada about bringing Cavill into "Black Adam" as Supes. When Hamada, who has been trying to get past the Zack Snyder era of DC movies, refused a Cavill cameo, Johnson reportedly went above his head to Warner Bros.' Pictures presidents Michael De Luca and Pamela Abdy who gave it the green light.

THR reports the mid-credits scene with Cavill was shot in September after Labor Day negotiations.

Johnson has been teasing for months about his desire to see Cavill suit up again. In an interview with ComicBook.com at San Diego Comic-Con, Johnson referred to Cavill as the Superman of our generation.

More recently, Johnson told "Good Day Chicago" reporter Jake Hamilton he's been "listening to the fans" to give them what they want.

"The most powerful and unstoppable force in the entire universe has been on the sidelines for too long," Johnson said, alluding to Superman.

Now that Cavill has appeared in 'Black Adam,' there are a few potential areas where we could next see Superman

According to THR, WB is very focused on bringing Superman back into the fold with some sort of "Man of Steel" sequel.

Johnson has also openly expressed his desire to see his DC antihero square off against Cavill's titan in some sort of "Black Adam vs. Superman" film. "Black Adam" producer Hiram Garcia told CinemaBlend the goal isn't to have a one-off between the two.

"We really want to craft a long-form of storytelling and show that these two characters exist in the same universe and are going to have to deal with each other often, either on the same or opposite sides," Garcia told CinemaBlend. "Hopefully they're going to clash at some point, but it's not just about a 'one fight' situation. That was never our dream. That does not reward the fans. Fans want to feel a journey between these guys knowing that these guys exist in the same universe."

It's likely we'll see movement on at least one of those projects, if not both, as long as "Black Adam" fares well at the box office despite very mixed reviews. Opening weekend predictions project the film to debut around $60 million, which would be on the high end for a Johnson-led film.

The biggest question is whether or not Cavill's return signals a chance that we'll see the Justice League reunite on the big screen. After all, posters and toys of the group's heroes are prominently showcased in "Black Adam." Before any team-up could occur, an "Aquaman" sequel and a standalone "Flash" movie are still scheduled for release in 2023.

At the least, Warner Bros. Discovery CEO David Zaslav has made it very clear that the Justice League's core heroes are a priority for the studio since taking over the studio in April.

In August, during a quarterly earnings call, Zaslav shared his ambitions to create a 10-year plan for DC movies that's similar to the Marvel Studios' machine in place at Disney. Zaslav specifically noted that Batman, Superman, Wonder Woman, and Aquaman are all popular characters that offer a "big opportunity" for the company.

Without someone to lead DC films at present, the future of its movie universe is a bit up in the air (a vigorous search for a new DC head continues). THR reported it's currently a bit like the "Wild West" at the studio with people, including James Gunn "The Suicide Squad," pitching projects.

Still, bringing Cavill back after a long hiatus at least offers a glimmer of hope that the studio is finally taking a step in the right direction in course-correcting its universe by listening to what fans want.