Sharing the shot on Instagram, the Girls star showed fans her convincing Peter Pan look with the iconic green costume and short reddish hair.
Williams captioned the picture with "The transformation begins! My first shoot as Pan." Then she added a tidbit about how pumped she really was to take on the iconic Disney role. "Fun fact: I was all ready to cut my hair, then was told by the folks who actually know what they're doing that a wig works better for everybody. So, December 4th, here we come. #wiglife #peterpanlive #nbc."
In the photo, Williams appears sitting atop a ship's mast in a typical Peter Pan pose while looking off into the distance with a half-smile.
But apparently, this is not the first time Williams has donned the leaf-colored getup, People magazine reported. A while back, the star shared another photo of herself dressed as Peter Pan when she was just a little girl.
"I have wanted to play Peter Pan since I was about 3 years old," Williams said when she first learned she'd landed the part of the boy that never grows up. "So this is a dream come true."
While on the Today show, Williams also said she was having lots of fun as rehearsals for the live show were beginning to heat up.
"The whole process just as it [is] sort of starting to get going is so fun," Williams went on. "Already I can only imagine what the next couple of weeks and months are going to bring."
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