Diane Lane Was 'Locked in a Room' With 'Superman' Script

Superman's mom keeps a tight lip.

This 'Superman' reboot is serious business. So serious, in fact, that actress Diane Lane she was locked in a room with the script and only allowed to read it once. Lane says she is sworn to secrecy regarding the film's plot.

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Lane, who plays the superhero's adoptive mother in the upcoming franchise reimagining dubbed 'Man of Steel,' says the film's story has been kept under extreme confidentiality.

"I read the script under lock and key," the 46 year-old actress told E! Online. "I was locked in a room with the script and was only allowed three hours with it."

Read: Diane Lane to Play Superman's Mother

When asked for more details about the film's plot, Lane couldn't add much, saying, "I nailed it into my memory. I'm really excited. I'm really not allowed to talk much about it, I think, but it does cover the entire range of years, from infancy on."

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Lane is part of a stellar cast that includes Kevin Costner as Superman's father, Jonathan Kent, Michael Shannon as the villain General Zod, Amy Adams as reporter Lois Lane and British actor Henry Cavill as the Man of Steel himself.

The film is set for a release in December 2012.

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