With reporting by Nicole Pajer

Dwayne "The Rock" Johnson is playing the bad guy (well, anti-hero) in Warner Bros' upcoming "Shazam..." And that's basically all we know about the movie. The multi-hyphenate, who also stars in the upcoming "Furious 7," has been bursting at the seams to talk about the superhero adaptation for years, teasing his involvement in bits and pieces from 2007 to September 3, when he officially, finally confirmed his role in the movie.

For those familiar with the franchise, though, beyond every piece of information, there's a key piece of info missing: who is playing the title role of Shazam? In the DC Comics the movie is based on, Shazam is secretly Billy Batson, a young boy able to take on fantastic strength and wisdom by uttering one word, "Shazam!" His opposite is Black Adam, who can use the same power but believes he is meant to rule the world. That's who The Rock is playing, by the way.

There's been different iterations of both characters, but when MTV News caught up with Johnson at the Los Angeles press day for "Furious 7," we discovered a little more about what makes Black Adam tick -- as well as whether the titular role has been cast yet.

"No..." Johnson said when asked if he knew who was stepping into Shazam's boots. "I can't wait to share more casting news by the way. No, we haven't picked a Shazam yet, and we have been working on the script. Half the scripts [have] already come in. Fantastic, very excited about it. And what I'm really excited about is -- because, again, I've lived with this character, and this opportunity for almost 10 years now, so it's like, in my DNA! I'm like a little kid, and it's the opportunity to create his journey, but that journey has to start out properly."

That journey has varied over the course of comic book continuity, but it seems like Black Adam will have a specific path that will skirt villainy, while not fully embracing it.

"And starting off properly is him not being a hero," Johnson continued. "That's got to be earned, so he starts off as a slave. And he's pissed off, and people are going to pay. But eventually down the line he'll become an anti-hero."

Adding to the complications of the movie is that unlike, say, "Man of Steel" where you cast the same actor as Clark Kent and Superman, "Shazam" has a very different problem. Billy Batson is a scrawny young kid, while Shazam is a muscled out superhuman adult. So will "Shazam" cast different actors for the roles, or somehow use both? Turns out, it's very much up in the air.

"I'm not quite too sure yet what we will do," Johnson said. "There's a lot of opportunity, with technology, maybe do a cool face replacement like they did in 'Captain America.' Maybe cast two separate actors, I'm not quite too sure."

We'll have to wait a good long while to find out, too: "Shazam" doesn't hit theaters until 2019.

To get your Rock fix, though, watch "Furious 7," which slams into theaters on April 3.