Warner Bros. and director Zack Snyder have been keeping mum on their upcoming 'Batman vs. Superman' film, despite letting slip that Lex Luthor will pop up as the new villain. With pre-production underway and the recent release of 'Man of Steel' on Blu-ray and DVD, though, stars Henry Cavill (Superman) and Ben Affleck (Batman) have chimed in on what we can expect from the upcoming superhero follow-up.

According to Cavill, we already secretly knew about Batman's inclusion in the 'Man of Steel' sequel, thanks to all those Easter eggs in the first film. "On the extras on the Blu-ray, we're going to get the opportunity to see Zack's references to other aspects of the DC universe. There's one obvious one which is now particularly obvious because of our next installment, which is involving Batman as well. We see Bruce Wayne Enterprises on the satellite in space."

Though he admittedly has little knowledge on the story of 'Batman vs. Superman,' he did reinforce a Lex Luthor appearance, saying, "We also see some references to LexCorp. I actually have no further knowledge of this next story, but there's a good chance Lex is going to be introduced soon or at some stage."

As for Affleck, who caused quite the uproar amongst Batman fans when he was first announced as the new Dark Knight, he seems to already know some details, though he refuses to delve deeper than the surface. Speaking with Entertainment Weekly, he said:

From what I’ve seen of what’s Zack is doing, it’s made me very excited. One of the nice things about being an actor in that movie is they show you all the stuff before anyone else gets to see it. So all the sort of world-creation, and the take on the character and the other characters is really exciting. And at the end of the day, the truth is it’s really directors that make movies work or not — especially these kinds of movies, where it’s about the whole world, and a rising tide lifts all ships. And if it all has integrity, if it all has a sense of realism, then it works. And if it doesn’t, than it doesn’t really matter what everyone’s doing [on the screen] because they just look like a bunch of Mexican wrestlers in suits.

Aside from Cavill and Affleck, 'Man of Steel' stars Amy Adams, Laurence Fishburne and Diane Lane will return for 'Batman vs. Superman,' which is slated for release on July 17, 2015. Furthermore, 'Girls' star Adam Driver is reportedly up for the role of Batman's sidekick/successor, Nightwing (aka Robin), and there's talk of a possible Wonder Woman appearance.

As Warner Bros. edges closer to the promised land that is the inevitable 'Justice League' movie, the studio seems poised to finally catch up to where the Marvel Cinematic Universe has traversed. So far, WB is looking to churn out two lower-budgeted films a year, and has its eyes set on Aquaman for a bigger cinematic romp. As for Cavill, he'd personally like to see the half-human, half-robot Cyborg get his share of the screen.

"What really intrigued me was Dr. Emil Hamilton's connection to S.T.A.R. Labs," he said of another 'Man of Steel' Easter egg. "Cyborg I think would make a wonderful character and an incredible bridge between both superhumans and humanity in a different way to Batman. So I don't know where he's going to come in or if he's going to come in, but that's one I'm particularly excited about. Other references I'm not too sure on, but we'll see where those lead."