In 2001, Robert Durst, heir to a two-billion-dollar fortune, was arrested for shoplifting. He was also on the run from a murder indictment-and suspected in the disappearance of his wife, Kathie. What transpired between Kathie's disappearance and the routine arrest was a 19-year, cross-country mystery of multiple identities that raised some baffling questions about one of the country's most prominent men.