I know Downton Abbey has received critical acclaim from television critics and won numerous accolades, including a Golden Globe Award for Best Miniseries or Television Film and a Primetime Emmy Award for Outstanding Miniseries. I know it was recognised by Guinness World Records as the most critically acclaimed English-language television series of 2011, and became the first international television series to receive the largest number of nominations in the history of the Primetime Emmy Awards, with twenty-seven in total.  I also know it was the most watched television series on both ITV and PBS, and subsequently became the most successful British costume drama series since the 1981 television serial of Brideshead Revisited.  By the third series, which ended tonight, it had become one of the most widely watched television shows in the world.  But why?  Who watches it?  I've never watched an episode, what am I missing?