Peter Pan Live is NBC's followup live production to The Sound of Music Live starring Carrie Underwood, which drew over 18.6 million live viewers last December.
Williams will be joined by Christopher Walken, who will play Captain Hook in the TV musical. She expressed her excitement by posting the cutest Instagram of herself as a young Peter Pan with the caption: "Thrilled to be playing Peter Pan live on NBC in December. I've been rehearsing for a REALLY long time."
Robert Greenblatt, chairman at NBC Entertainment called Williams said that NBC "couldn’t be happier that Allison Williams is our Peter Pan," adding, "She's a lovely rising star on the award-winning show Girls -- where she occasionally shows off her incredible vocal talent -- and we think she will bring the perfect blend of 'boyish' vulnerability and bravado to save the day against Christopher Walken’s powerful Captain Hook."
NBC had reportedly expressed interest in Kristen Bell for the titular role, but couldn't get her due to her commitment to Showtime's House of Lies.