Diane Lane has joined Zack Snyder’s Superman project and will play the hero’s mother Martha Kent.

Lane, an Oscar nominee for Unfaithful, will star opposite Henry Cavill in the dual lead role of Clark Kent and the Man Of Steel.

“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. “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.”

Charles Roven, Emma Thomas, Christopher Nolan and Deborah Snyder are producers and Legendary Pictures head Thomas Tull and Lloyd Phillips serve as executive producers.

David S Goyer wrote the screenplay from a story idea he co-authored with his Batman Begins and The Dark Knight collaborator Nolan. Warner Bros holds worldwide rights and has earmarked a December 2012 release.