Yvonne Jaqueline Strzechowski (born 30 July 1982), better known by the stage name Yvonne Strahovski, is an Australian actress. She is best known for playing CIA agent Sarah Walker in the NBC television series "Chuck" from 2007 until 2012. She also appeared as Hannah McKay in the Showtime series "Dexter" from 2012 until 2013. Her movie roles include "Killer Elite" (2011), "The Guilt Trip" (2013) and "I, Frankenstein" (2014). She also played Miranda Lawson in the "Mass Effect" video games and CIA agent Kate Morgan in "24": "".