Known for her starring role as Marnie Michaels on the hit HBO drama Girls. She wrote and starred in a series of sketches for the comedy website Funny or Die, playing a newlywed Kate Middleton.
She studied at Yale University, where she was a member of the improvisational comedy troupe Just Add Water.
In 2013, she played Jillian in three episodes on The Mindy Project.
Her father Brian Williams began anchoring NBC Nightly News in 1993. In 2015 she married Ricky Van Veen.
Lena Dunham created and co-starred in the series Girls.
