Hear Allison Williams Sing In New 'Peter Pan Live' Footage

Fun fact: 'I Won't Grow Up' also applies to 'Girls.'

No, this isn't another trailer for "Girls" in which Marnie sings and everyone is embarrassed. This is Allison Williams singing for real in "Peter Pan Live!"

The new promo for the musical event just hit the web, and in addition to listening Williams sing as Peter for the first time, we get to hear Christopher Walken's Captain Hook as his Walkeniest.

"Who's the greatest villain........... of all time?"

We'll be able to see how it all goes down live when "Peter Pan" hits the airwaves on December 4 on NBC.