Watch the full-length episode at http://video.pbs.org/video/2365419108/?Utm_source=youtube&utm_medium=pbsofficial&utm_campaign=mast_covefullprogram (US Only) Historical advisor to the series Alastair Bruce explores the social and technical nuances of the point-to-point horse race of Downton Abbey, Season 5, Episode 6, as seen on MASTERPIECE on PBS. #DowntonPBS