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, Erin McGuire on the short-lived TV show Trust Me, and CIA Agent Lena Smith on the USA Network show Covert Affairs. She portrays Marla Jameson. Clarke was born in St. Louis, Missouri, the daughter of Carolyn, a homemaker, and Ernest Clarke, an engineer. She attended John Burroughs School in St. Louis…