NATIONAL TREASURE 2 is already filming in Washington, DC so it’s surprising that no casting details have been announced yet. Well that’s what JoBlo.com is here for! We’ve got the scoop on which Academy Award favorites have joined the cast of BOOK OF SECRETS. Signing on to play Nicolas Cage’s mother, Emily Gates, is recent Oscar-winner Helen Mirren. She’s there to help link Cage’s Ben Gates to his family’s connection to John Wilkes Booth and the mysterious Knights of the Gold Circle. Now we have our protagonists in Cage and Mirren but a movie is only as strong as its bad guy and Disney has managed to cast one of the best “bad guy” actors around: four time Oscar nominee Ed Harris. Harris will star as Jeb Wilkinson, who has some information about Gates’ father and aligns himself as an ally, but…well, you can guess where it goes from here. Talk about some pretty impressive additions to the cast!… Returning to star in SECRETS from the first film are Diane Kruger, Justin Bartha and Harvey Keitel. Disney has BOOK OF SECRETS scheduled for release on December 17th of this year.