STAGE TUBE: Watch Allison Williams' Tearful Post-PETER PAN Reaction

On Thursday night, Allison Williams as the title character led the cast of PETER PAN LIVE! on NBC. Below, watch this sweet moment after the show in which the whole cast cheers for Williams right after the show, and she shares a tender moment with Kelli O'Hara.

Williams is best known as Marnie in HBO's critically acclaimed Judd Apatow/Lena Dunham series "Girls." The poignant comedy is about four friends living in Brooklyn a few years out of college. It debuted on HBO in 2012 and was nominated for a Best Comedy Emmy and Best Comedy Golden Globe. Season 5 premieres in January 2015.

In 2011, Williams starred as Kate Middleton in a four-part, self-written original miniseries for Funny or Die called " Will & Kate: Before Happily Ever After." She made a guest appearance on Fox's "The Mindy Project" in 2013.

Williams graduated from Yale University in 2010 and afterwards began working on a video released on YouTube, "Mad Men Theme Song... With a Twist." She moved to Los Angeles just before releasing the video, which quickly became a viral sensation and garnered much attention in the blog and entertainment world. Among the video's fans were Judd Apatow and the executives at HBO, who, upon seeing the video, reached out to Williams for an audition for "Girls." Ironically, within a month of moving to Los Angeles, she was back in New York filming the pilot episode.

While she may have found success quickly, Williams has been honing her craft for years. She has been involved in theater since an early age, and while at Yale refined her improv skills as a member of the improvisational comedy group Just Add Water. She graduated with a BA in English and is trained in acting and singing as well.

Born and raised in Connecticut, Williams declared to her parents at the age of 4 that she wanted to be an actress. Brian and Jane Williams - who required their daughter to graduate from college before pursuing an acting career - are both involved in the media. Jane has a weekly radio show on Bloomberg radio called "Bloomberg Edu," which addresses education issues in the United States. Brian is the anchor and managing editor of "NBC Nightly News."
Williams enjoys singing, improvisational comedy and writing fiction. She currently splits her time between Los Angeles and New York City.

On Thursday night, December 4th, NBC presented PETER PAN LIVE!, a bold new LIVE television production of the classic Broadway musical that will gather friends, families and anyone who refuses to ever grow up. Following in the footsteps of the phenomenally successful The Sound of Music LIVE! - which drew over 44 million viewers - comes this musical masterpiece that tells the beloved story of Peter Pan, the mischievous little boy who ran away to Neverland. It included show-stopping stars, stunning costumes, extravagant sets and delightful music.