While rumors continue to swirl that "Superman" director Zack Snyder is eyeing Viggo Mortensen for a villainous role in the rebooted comic book franchise, Warner Bros. has officially announced the casting of a good guy — or, we should say, a good mom.

Diane Lane is officially onboard to play Martha Kent, the adoptive mother of Clark Kent, according to a studio press release.

"This was a very important piece of casting for me because Martha Kent is the woman whose values helped shape the man we know as Superman," Snyder said in a statement. "We are thrilled to have Diane in the role because she can convey the wisdom and the wonder of a woman whose son has powers beyond her imagination." The casting doesn't mark the first time the Oscar-winning actress has entered a high-profile comic book adaptation. In the mid-'90s, she appeared alongside Sylvester Stallone in "Judge Dredd." She's also co-starred in action- and thriller-oriented fare like "Jumper," "Murder at 1600" and the barely seen "Killshot."

Lane joins Henry Cavill, who's playing the Man of Steel, as confirmed "Superman" castmembers. Mortensen has been rumored for the role of General Zod, the nefarious alien at the heart of 1980's "Superman II." Kevin Costner has been mentioned as a possible choice for Jonathan Kent, the husband of Martha and the adoptive father of Clark.

Directed by Snyder, produced by "Dark Knight" guru Christopher Nolan and with a screenplay penned by David S. Goyer, the new "Superman" flick is slated for a December 2012 release date.

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