Sienna Miller spent the early years of her career in the flashing bulbs and shouted questions of media outlets fascinated by her relationships and her style. But standout performances in movies like Factory Girl, Foxcatcher and American Woman have forced a change of subject. In this week’s “Sunday Sitdown,” Willie Geist gets together with the star to talk about her new Netflix series, Anatomy of a Scandal, which has her tapping into those trying years in the spotlight.