Fans of DC Comics' Captain Marvel mythology were undoubtedly ecstatic to learn a few years ago that Dwayne Johnson had officially been cast in the villainous role of Black Adam in the DC Films universe. At the time, it was widely assumed that Johnson would star in a movie opposite the heroic Shazam, given that the two are sworn enemies in the source material.

However, fans were ultimately disappointed to learn that that wasn't going to be the case. Instead, in David F. Sandberg's Shazam!, the title superhero will instead go up against another one of his foes, Doctor Sivana. Given that Johnson is attached to the role, and that Shazam! might obviously open the door for a sequel, could the solo film set up the character in any way?

That is the question that MTV asked the cast and director of Shazam! during an interview at Comic-Con International in San Diego. In answer, Sandberg said that Black Adam was being saved "mostly for another tale," but he did play it slightly coy, engaging in evasive maneuvers that ended with him saying "There are a lot of Easter eggs and references and things like that in this movie."

RELATED: Shazam! Is Proof the DCEU Doesn’t Need a Reboot

Following the release of the SDCC trailer, it's now clear that the movie borrows a lot of elements from the New 52 Shazam comic book, a comic that featured both Doctor Sivana and Black Adam prominently. If Sivana is being used in the first film, could his story directly tie into the arrival of Black Adam in the DC Films universe?

While it's not definitive, these Easter eggs and references that Sandberg mention might serve as seeds planted to a bigger picture that involves Johnson's character. If Warner Bros. finds a way to keep it all secret, it would certainly be a real treat for fans to have Johnson make a surprise appearance in the after-credits scene of the film.

RELATED: Worlds of DC Is the Perfect Name For Warner Bros.’ Superhero Universe

Arriving April 5, 2019, director David F. Sandberg’s Shazam! stars Asher Angel as Billy Batson, Zachary Levi as Shazam, Mark Strong as Dr. Thaddeus Sivana, Djimon Hounsou as an ancient wizard named Shazam, Grace Fulton as Mary Bromfield, Jack Dylan Grazer as Frederick “Freddy” Freeman, Ian Chen as Eugene Choi, Jovan Armand as Pedro Peña, Faithe Herman as Darla Dudley, Cooper Andrews as Victor Vásquez and Marta Milans as Rosa Vásquez.