Ehle, 43, is best known for her roles in "Zero Dark Thirty," "Contagion" and "The Ides of March."
She would play Clarla in "50 Shades," the Southern seductress and mother to Anastasia, the lead female role.
Confirmed cast members include "Sons of Anarchy" star Charlie Hunnam and actress Dakota Johnson as Christian Grey and Anastasia. Filming for the movie begins in the fall for an August 2014 release.
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