A trailer for Downton Abbey's Christmas Special was released Monday revealing details about upcoming plot lines for the popular drama series. Screenshot

"Downton Abbey" fans have just 16 days until the highly anticipated Season 4 Christmas Special. When we last left the Crawleys, Mary was being chased by two suitors, Edith was contemplating a Swiss vacation to avoid revealing her illegitimate pregnancy and Rose “stirred the pot” with her romance with the black American musician, Jack Ross.

So where does that leave us for the Christmas Special?

Well, it’s not at Downton. The plot picks up in London, where the family and servants are at Grantham House preparing for Rose’s introduction to society – which will take place at Buckingham Palace. Cora's mother, Martha Levinson (Shirley MacLaine) refuses to miss the occasion and travels with her son, Harold (Paul Giamatti), from New York to see the who’s who of London high society. Apparently the pair make a particular impression on Lord Aysgarth, played by James Fox.

Isobel Crawley (Penelope Wilton) – who kicked it off with Lady Mary’s godfather last episode, may still be debating whether to pursue that romance. Spoilers hint at Edith continuing to contemplate a “moral dilemma” – i.e. her pregnancy.

Illegitimate children may not be the only scandal facing the Crawleys. Spoilers described another scandal the family is implicated in that “threatens to engulf the monarch.” Robert (Hugh Bonneville) takes action to make sure that both his family and the royal one are protected.

Downstairs, Daisy, who took the high road last episode when she gave Alfred a parting gift when he left the household for cooking school, apparently receives an “unexpected invitation” in letter form that leaves her smiling. Carson appears to be in high spirits, and gives the staff a “special day out.”

The teaser for the episode reveals ornate scenes that depict Buckingham Palace as Rose and other debutantes are presented to society. The interior scenes were filmed at Lancaster House – a mansion in London’s West End. The Crawleys' London residence was filmed at the beach at West Wittering in Sussex and Basildon Park in Berkshire.

The Christmas Special will air on the UK’s ITV on Dec. 25. The latest season had the highest rating the period-piece has ever received in the UK with 12 million viewers. Season 4 will begin airing in the U.S. on Masterpiece PBS beginning Jan. 5, 2014.