By Stephanie Gosk
NBC News

LONDON –  Full disclosure: I am a total sucker for the period drama, never mind a period drama starring Dame Maggie Smith.  So it was with very little arm-twisting that my “Nightly News” producers in New York convinced me to do a story on the success of the PBS series “Downton Abbey.”  Set in the early 1900s it is oh-so-very-proper, oh-so-very-British and oh-so-very-much my weakness.

"Downton Abbey" belongs to Lord and Lady Grantham.  Their family life, and the lives of those people downstairs who make their family life possible, drive the show’s stories of love, betrayal, and tragedy. Cue the dramatic soundtrack.

The much-anticipated second season, which has already concluded in the U.K., premiered Sunday in the U.S.

The creator, Julian Fellowes, 62, is a master of this genre.  He wrote the screenplay and won an Oscar for Robert Altman’s “Gosford Park” in 2001, another British period drama set in the early 1900s.  It turns out Fellowes, whose full name is Baron Fellowes of West Stafford (no stranger to the upper crust of British society) is fascinated with that dynamic moment in history.  We found him, his eccentric wife Emma Fellowes, and their two dogs in a sprawling manor house in Dorset. 

Once we had tea (an immediate “must”) and Christmas Cake (obviously an acquired taste), I had a chance to ask Fellowes about his inspiration.

“The change between 1910 and 1920 was colossal. The change between 1910 and 1930 is almost unbelievable,” he said, “So you have quite a short period in terms of narrative giving you constantly altering problems and situations.”

Already an expert on the era, Fellowes wrote the script for the first season the same year they started shooting. Finding the location was also a swift process.  The Fellowes family are very close friends with the Carnarvons down the road.  Lord and Lady Carnarvon own Highclere Castle, the real Downton Abbey. 

Through no coincidence, the history of the estate occasionally parallels the show especially in the second season, which I won’t spoil.  I have already seen in its entirety including the final two-hour season finale, which aired, dramatically and heart wrenchingly, on Christmas day here in Britain. Cue the soundtrack again. 

Highclere Castle, built in the 17th century, has always been in the Carnarvon family.  It is open for tours and can be rented out for pheasant hunts and weddings, but it is also still the family home. Lady Carnarvon met us in the salon, which she assured me is still used by the ladies for a good “chin wag” after dinner while the men in their smoking jackets drink port and smoke cigars elsewhere.   It is the same room used by the ladies of “Downton Abbey” with very little furniture moved or added.   

“We hoped for 4 or 5 million viewers in this country, Stephanie,” she said. “We thought it would be a really nice program on a Sunday evening and we were nervously waiting for the viewing figures.”

No need for concern.  By the time that finale aired on Christmas day, 11.9 million people watched.  For those who don’t readily know the population of Britain, that is about one sixth of all Britons: a huge audience.

The Guinness Book of World Records calls “Downton Abbey” the most highly acclaimed TV show of all time.   It won six Emmys last year, is nominated for four Golden Globes this year, and there are likely more awards to come.

In January 2011, when the show first debuted in the U.S., The Associated Press reported each of its first four episodes averaged more than 6 million viewers, according to Nielsen Co. ratings.

So how does a British period drama about the Edwardian age transcend the decades and become popular? 

Lady Carnarvon attributes the show’s success, in large part, to its characters. “This is all about the family.  The house today – it’s still about the family here upstairs and downstairs,” she said.   

Fellowes agreed.

“We really just have a group of people who are living and working under this roof and they're trying to make the best of it,” he said. “They're trying to get through their lives as best as they can, as we all are.”