Maybe Marnie Michaels will never really grow up. NBC cast “Girls” star Allison Williams to play Peter Pan in “Peter Pan Live,” which will be broadcast on Dec. 4.

“Peter Pan Live” is the network’s follow-up to last year’s “The Sound of Music,” which starred Stephen Moyer and Carrie Underwood, and garnered 18.6 million viewers.

NBC Chairman Robert Greenblatt had previously suggested that the network would cast a man to play Peter Pan, but clearly it went in a different direction:

Dreams do come true! #Girls star Allison Williams will play Peter Pan in #PeterPanLive! pic.twitter.com/b69aVLj9tg

— NBC (@nbc) July 30, 2014

Williams’ vocal abilities have been highlighted on “Girls,” but her character Marnie’s budding music career is used as a running joke. Let’s hope her rendition of “I Won’t Grow Up” goes over better.