January Kristen Jones (born January 5, 1978) is an American actress and model. She is best known for playing Betty Draper in the television series Mad Men (2007–15), as well as for notable roles in American Wedding (2003), We are Marshall (2006), and in the 2011 films Unknown, Seeking Justice and in which she starred as Emma Frost. Since 2015, Jones has been starring as Melissa Chartres in the Fox series The Last Man on Earth.