Who Are They? Olivia Williams is Adelle DeWitt
Olivia Williams is Adelle DeWitt - Iron Fist, Doll Heart?
Olivia Williams - IMDB | Wikipedia | Adelle DeWitt Forum
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“40-something, beautiful, sophisticated, cold as an Alp. Runs the Dollhouse with an efficiency that is both ruthless and protective. Would die before she showed anyone how lonely she is.” - Televisionary

[...] is the fact that Claire was originally going to be an older woman, perhaps around the same age as Adelle deWitt, who is being portrayed by Olivia Williams. That would have created an interesting dynamic, [...]