Katherine Litwack (born June 13, 1986), known professionally as Kat Dennings, is an American actress. Starting with a role in an episode of the HBO dramedy series Sex and the City, Dennings has since appeared in the films The 40-Year-Old Virgin, Big Momma's House 2, Charlie Bartlett, Raise Your Voice, The House Bunny, Defendor, Nick and Norah's Infinite Playlist, Thor, and . Since 2011, she stars alongside Beth Behrs in the CBS sitcom 2 Broke Girls.