Sarah Clarke (born February 16, 1972) is an American actress, best known for her role as Nina Myers on 24, and also for her roles as Renée Dwyer, Bella Swan's mother, in the 2008 film Twilight.Clarke was born in St. Louis, Missouri, the daughter of Carolyn, a homemaker, and Ernest Clarke, an engineer.[1] She attended John Burroughs School in St. Louis, Missouri (along with Mad Men star Jon Hamm, who was her prom date), and Indiana University, where she studied Fine Arts and Italian.